smart diff to testutil.GatherAndCompare (#998)
* added smart diff to testutil.GatherAndCompare Signed-off-by: Sourik Ghosh <sourikghosh31@gmail.com> * v2 testuitls added for better diff Signed-off-by: Sourik Ghosh <sourikghosh31@gmail.com> * replaced CollectAndCompare to CollectAndCompareV2 in testutil_test Signed-off-by: Sourik Ghosh <sourikghosh31@gmail.com> * renamed methods from v2 to withT Signed-off-by: Sourik Ghosh <sourikghosh31@gmail.com> * replaced testify with custom diff func Signed-off-by: Sourik Ghosh <sourikghosh31@gmail.com> * difflib GetUnifiedDiffString added with test Signed-off-by: Sourik Ghosh <sourikghosh31@gmail.com> * license meta data added to file Signed-off-by: Sourik Ghosh <sourikghosh31@gmail.com> * moved difflib to internal Signed-off-by: Sourik Ghosh <sourikghosh31@gmail.com>
This commit is contained in:
Sourik Ghosh
GitHub
parent
0c691ed35f
commit
cd90f33be8
1
go.mod
1
go.mod
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@ -3,6 +3,7 @@ module github.com/prometheus/client_golang
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require (
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github.com/beorn7/perks v1.0.1
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github.com/cespare/xxhash/v2 v2.1.2
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github.com/davecgh/go-spew v1.1.1
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github.com/golang/protobuf v1.5.2
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github.com/jpillora/backoff v1.0.0 // indirect
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github.com/json-iterator/go v1.1.12
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@ -0,0 +1,649 @@
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// Copyright 2022 The Prometheus Authors
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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//
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// It provides tools to compare sequences of strings and generate textual diffs.
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//
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// Maintaining `GetUnifiedDiffString` here because original repository
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// (https://github.com/pmezard/go-difflib) is no loger maintained.
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package internal
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import (
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"bufio"
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"bytes"
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"fmt"
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"io"
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"strings"
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)
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func min(a, b int) int {
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if a < b {
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return a
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}
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return b
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}
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func max(a, b int) int {
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if a > b {
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return a
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}
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return b
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}
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func calculateRatio(matches, length int) float64 {
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if length > 0 {
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return 2.0 * float64(matches) / float64(length)
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}
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return 1.0
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}
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type Match struct {
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A int
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B int
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Size int
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}
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type OpCode struct {
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Tag byte
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I1 int
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I2 int
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J1 int
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J2 int
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}
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// SequenceMatcher compares sequence of strings. The basic
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// algorithm predates, and is a little fancier than, an algorithm
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// published in the late 1980's by Ratcliff and Obershelp under the
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// hyperbolic name "gestalt pattern matching". The basic idea is to find
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// the longest contiguous matching subsequence that contains no "junk"
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// elements (R-O doesn't address junk). The same idea is then applied
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// recursively to the pieces of the sequences to the left and to the right
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// of the matching subsequence. This does not yield minimal edit
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// sequences, but does tend to yield matches that "look right" to people.
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//
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// SequenceMatcher tries to compute a "human-friendly diff" between two
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// sequences. Unlike e.g. UNIX(tm) diff, the fundamental notion is the
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// longest *contiguous* & junk-free matching subsequence. That's what
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// catches peoples' eyes. The Windows(tm) windiff has another interesting
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// notion, pairing up elements that appear uniquely in each sequence.
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// That, and the method here, appear to yield more intuitive difference
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// reports than does diff. This method appears to be the least vulnerable
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// to synching up on blocks of "junk lines", though (like blank lines in
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// ordinary text files, or maybe "<P>" lines in HTML files). That may be
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// because this is the only method of the 3 that has a *concept* of
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// "junk" <wink>.
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//
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// Timing: Basic R-O is cubic time worst case and quadratic time expected
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// case. SequenceMatcher is quadratic time for the worst case and has
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// expected-case behavior dependent in a complicated way on how many
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// elements the sequences have in common; best case time is linear.
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type SequenceMatcher struct {
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a []string
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b []string
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b2j map[string][]int
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IsJunk func(string) bool
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autoJunk bool
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bJunk map[string]struct{}
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matchingBlocks []Match
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fullBCount map[string]int
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bPopular map[string]struct{}
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opCodes []OpCode
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}
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func NewMatcher(a, b []string) *SequenceMatcher {
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m := SequenceMatcher{autoJunk: true}
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m.SetSeqs(a, b)
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return &m
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}
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func NewMatcherWithJunk(a, b []string, autoJunk bool,
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isJunk func(string) bool) *SequenceMatcher {
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m := SequenceMatcher{IsJunk: isJunk, autoJunk: autoJunk}
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m.SetSeqs(a, b)
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return &m
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}
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// Set two sequences to be compared.
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func (m *SequenceMatcher) SetSeqs(a, b []string) {
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m.SetSeq1(a)
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m.SetSeq2(b)
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}
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// Set the first sequence to be compared. The second sequence to be compared is
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// not changed.
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//
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// SequenceMatcher computes and caches detailed information about the second
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// sequence, so if you want to compare one sequence S against many sequences,
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// use .SetSeq2(s) once and call .SetSeq1(x) repeatedly for each of the other
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// sequences.
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//
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// See also SetSeqs() and SetSeq2().
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func (m *SequenceMatcher) SetSeq1(a []string) {
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if &a == &m.a {
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return
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}
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m.a = a
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m.matchingBlocks = nil
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m.opCodes = nil
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}
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// Set the second sequence to be compared. The first sequence to be compared is
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// not changed.
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func (m *SequenceMatcher) SetSeq2(b []string) {
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if &b == &m.b {
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return
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}
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m.b = b
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m.matchingBlocks = nil
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m.opCodes = nil
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m.fullBCount = nil
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m.chainB()
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}
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func (m *SequenceMatcher) chainB() {
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// Populate line -> index mapping
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b2j := map[string][]int{}
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for i, s := range m.b {
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indices := b2j[s]
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indices = append(indices, i)
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b2j[s] = indices
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}
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// Purge junk elements
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m.bJunk = map[string]struct{}{}
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if m.IsJunk != nil {
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junk := m.bJunk
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for s, _ := range b2j {
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if m.IsJunk(s) {
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junk[s] = struct{}{}
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}
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}
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for s, _ := range junk {
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delete(b2j, s)
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}
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}
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// Purge remaining popular elements
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popular := map[string]struct{}{}
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n := len(m.b)
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if m.autoJunk && n >= 200 {
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ntest := n/100 + 1
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for s, indices := range b2j {
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if len(indices) > ntest {
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popular[s] = struct{}{}
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}
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}
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for s, _ := range popular {
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delete(b2j, s)
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}
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}
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m.bPopular = popular
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m.b2j = b2j
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}
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func (m *SequenceMatcher) isBJunk(s string) bool {
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_, ok := m.bJunk[s]
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return ok
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}
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// Find longest matching block in a[alo:ahi] and b[blo:bhi].
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//
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// If IsJunk is not defined:
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//
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// Return (i,j,k) such that a[i:i+k] is equal to b[j:j+k], where
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// alo <= i <= i+k <= ahi
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// blo <= j <= j+k <= bhi
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// and for all (i',j',k') meeting those conditions,
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// k >= k'
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// i <= i'
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// and if i == i', j <= j'
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//
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// In other words, of all maximal matching blocks, return one that
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// starts earliest in a, and of all those maximal matching blocks that
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// start earliest in a, return the one that starts earliest in b.
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//
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// If IsJunk is defined, first the longest matching block is
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// determined as above, but with the additional restriction that no
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// junk element appears in the block. Then that block is extended as
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// far as possible by matching (only) junk elements on both sides. So
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// the resulting block never matches on junk except as identical junk
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// happens to be adjacent to an "interesting" match.
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//
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// If no blocks match, return (alo, blo, 0).
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func (m *SequenceMatcher) findLongestMatch(alo, ahi, blo, bhi int) Match {
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// CAUTION: stripping common prefix or suffix would be incorrect.
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// E.g.,
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// ab
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// acab
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// Longest matching block is "ab", but if common prefix is
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// stripped, it's "a" (tied with "b"). UNIX(tm) diff does so
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// strip, so ends up claiming that ab is changed to acab by
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// inserting "ca" in the middle. That's minimal but unintuitive:
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// "it's obvious" that someone inserted "ac" at the front.
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// Windiff ends up at the same place as diff, but by pairing up
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// the unique 'b's and then matching the first two 'a's.
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besti, bestj, bestsize := alo, blo, 0
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// find longest junk-free match
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// during an iteration of the loop, j2len[j] = length of longest
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// junk-free match ending with a[i-1] and b[j]
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j2len := map[int]int{}
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for i := alo; i != ahi; i++ {
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// look at all instances of a[i] in b; note that because
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// b2j has no junk keys, the loop is skipped if a[i] is junk
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newj2len := map[int]int{}
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for _, j := range m.b2j[m.a[i]] {
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// a[i] matches b[j]
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if j < blo {
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continue
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}
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if j >= bhi {
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break
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}
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k := j2len[j-1] + 1
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newj2len[j] = k
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if k > bestsize {
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besti, bestj, bestsize = i-k+1, j-k+1, k
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}
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}
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j2len = newj2len
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}
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// Extend the best by non-junk elements on each end. In particular,
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// "popular" non-junk elements aren't in b2j, which greatly speeds
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// the inner loop above, but also means "the best" match so far
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// doesn't contain any junk *or* popular non-junk elements.
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for besti > alo && bestj > blo && !m.isBJunk(m.b[bestj-1]) &&
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m.a[besti-1] == m.b[bestj-1] {
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besti, bestj, bestsize = besti-1, bestj-1, bestsize+1
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}
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for besti+bestsize < ahi && bestj+bestsize < bhi &&
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!m.isBJunk(m.b[bestj+bestsize]) &&
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m.a[besti+bestsize] == m.b[bestj+bestsize] {
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bestsize += 1
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}
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// Now that we have a wholly interesting match (albeit possibly
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// empty!), we may as well suck up the matching junk on each
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// side of it too. Can't think of a good reason not to, and it
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// saves post-processing the (possibly considerable) expense of
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// figuring out what to do with it. In the case of an empty
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// interesting match, this is clearly the right thing to do,
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// because no other kind of match is possible in the regions.
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for besti > alo && bestj > blo && m.isBJunk(m.b[bestj-1]) &&
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m.a[besti-1] == m.b[bestj-1] {
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besti, bestj, bestsize = besti-1, bestj-1, bestsize+1
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}
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for besti+bestsize < ahi && bestj+bestsize < bhi &&
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m.isBJunk(m.b[bestj+bestsize]) &&
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m.a[besti+bestsize] == m.b[bestj+bestsize] {
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bestsize += 1
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}
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return Match{A: besti, B: bestj, Size: bestsize}
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}
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// Return list of triples describing matching subsequences.
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//
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// Each triple is of the form (i, j, n), and means that
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// a[i:i+n] == b[j:j+n]. The triples are monotonically increasing in
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// i and in j. It's also guaranteed that if (i, j, n) and (i', j', n') are
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// adjacent triples in the list, and the second is not the last triple in the
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// list, then i+n != i' or j+n != j'. IOW, adjacent triples never describe
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// adjacent equal blocks.
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//
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// The last triple is a dummy, (len(a), len(b), 0), and is the only
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// triple with n==0.
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func (m *SequenceMatcher) GetMatchingBlocks() []Match {
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if m.matchingBlocks != nil {
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return m.matchingBlocks
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}
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var matchBlocks func(alo, ahi, blo, bhi int, matched []Match) []Match
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matchBlocks = func(alo, ahi, blo, bhi int, matched []Match) []Match {
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match := m.findLongestMatch(alo, ahi, blo, bhi)
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i, j, k := match.A, match.B, match.Size
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if match.Size > 0 {
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if alo < i && blo < j {
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matched = matchBlocks(alo, i, blo, j, matched)
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}
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matched = append(matched, match)
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if i+k < ahi && j+k < bhi {
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matched = matchBlocks(i+k, ahi, j+k, bhi, matched)
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}
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}
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return matched
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}
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matched := matchBlocks(0, len(m.a), 0, len(m.b), nil)
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// It's possible that we have adjacent equal blocks in the
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// matching_blocks list now.
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nonAdjacent := []Match{}
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i1, j1, k1 := 0, 0, 0
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for _, b := range matched {
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// Is this block adjacent to i1, j1, k1?
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i2, j2, k2 := b.A, b.B, b.Size
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if i1+k1 == i2 && j1+k1 == j2 {
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// Yes, so collapse them -- this just increases the length of
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// the first block by the length of the second, and the first
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// block so lengthened remains the block to compare against.
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k1 += k2
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} else {
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// Not adjacent. Remember the first block (k1==0 means it's
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// the dummy we started with), and make the second block the
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// new block to compare against.
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if k1 > 0 {
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nonAdjacent = append(nonAdjacent, Match{i1, j1, k1})
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}
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i1, j1, k1 = i2, j2, k2
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}
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}
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if k1 > 0 {
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nonAdjacent = append(nonAdjacent, Match{i1, j1, k1})
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}
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nonAdjacent = append(nonAdjacent, Match{len(m.a), len(m.b), 0})
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m.matchingBlocks = nonAdjacent
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return m.matchingBlocks
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}
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// Return list of 5-tuples describing how to turn a into b.
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//
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// Each tuple is of the form (tag, i1, i2, j1, j2). The first tuple
|
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// has i1 == j1 == 0, and remaining tuples have i1 == the i2 from the
|
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// tuple preceding it, and likewise for j1 == the previous j2.
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//
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// The tags are characters, with these meanings:
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//
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// 'r' (replace): a[i1:i2] should be replaced by b[j1:j2]
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//
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// 'd' (delete): a[i1:i2] should be deleted, j1==j2 in this case.
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//
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// 'i' (insert): b[j1:j2] should be inserted at a[i1:i1], i1==i2 in this case.
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//
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// 'e' (equal): a[i1:i2] == b[j1:j2]
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func (m *SequenceMatcher) GetOpCodes() []OpCode {
|
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if m.opCodes != nil {
|
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return m.opCodes
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}
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i, j := 0, 0
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matching := m.GetMatchingBlocks()
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opCodes := make([]OpCode, 0, len(matching))
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for _, m := range matching {
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// invariant: we've pumped out correct diffs to change
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// a[:i] into b[:j], and the next matching block is
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// a[ai:ai+size] == b[bj:bj+size]. So we need to pump
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// out a diff to change a[i:ai] into b[j:bj], pump out
|
||||
// the matching block, and move (i,j) beyond the match
|
||||
ai, bj, size := m.A, m.B, m.Size
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tag := byte(0)
|
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if i < ai && j < bj {
|
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tag = 'r'
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||||
} else if i < ai {
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tag = 'd'
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} else if j < bj {
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tag = 'i'
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}
|
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if tag > 0 {
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opCodes = append(opCodes, OpCode{tag, i, ai, j, bj})
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}
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i, j = ai+size, bj+size
|
||||
// the list of matching blocks is terminated by a
|
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// sentinel with size 0
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||||
if size > 0 {
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opCodes = append(opCodes, OpCode{'e', ai, i, bj, j})
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||||
}
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||||
}
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m.opCodes = opCodes
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return m.opCodes
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||||
}
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||||
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||||
// Isolate change clusters by eliminating ranges with no changes.
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//
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// Return a generator of groups with up to n lines of context.
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||||
// Each group is in the same format as returned by GetOpCodes().
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||||
func (m *SequenceMatcher) GetGroupedOpCodes(n int) [][]OpCode {
|
||||
if n < 0 {
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||||
n = 3
|
||||
}
|
||||
codes := m.GetOpCodes()
|
||||
if len(codes) == 0 {
|
||||
codes = []OpCode{{'e', 0, 1, 0, 1}}
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||||
}
|
||||
// Fixup leading and trailing groups if they show no changes.
|
||||
if codes[0].Tag == 'e' {
|
||||
c := codes[0]
|
||||
i1, i2, j1, j2 := c.I1, c.I2, c.J1, c.J2
|
||||
codes[0] = OpCode{c.Tag, max(i1, i2-n), i2, max(j1, j2-n), j2}
|
||||
}
|
||||
if codes[len(codes)-1].Tag == 'e' {
|
||||
c := codes[len(codes)-1]
|
||||
i1, i2, j1, j2 := c.I1, c.I2, c.J1, c.J2
|
||||
codes[len(codes)-1] = OpCode{c.Tag, i1, min(i2, i1+n), j1, min(j2, j1+n)}
|
||||
}
|
||||
nn := n + n
|
||||
groups := [][]OpCode{}
|
||||
group := []OpCode{}
|
||||
for _, c := range codes {
|
||||
i1, i2, j1, j2 := c.I1, c.I2, c.J1, c.J2
|
||||
// End the current group and start a new one whenever
|
||||
// there is a large range with no changes.
|
||||
if c.Tag == 'e' && i2-i1 > nn {
|
||||
group = append(group, OpCode{c.Tag, i1, min(i2, i1+n),
|
||||
j1, min(j2, j1+n)})
|
||||
groups = append(groups, group)
|
||||
group = []OpCode{}
|
||||
i1, j1 = max(i1, i2-n), max(j1, j2-n)
|
||||
}
|
||||
group = append(group, OpCode{c.Tag, i1, i2, j1, j2})
|
||||
}
|
||||
if len(group) > 0 && !(len(group) == 1 && group[0].Tag == 'e') {
|
||||
groups = append(groups, group)
|
||||
}
|
||||
return groups
|
||||
}
|
||||
|
||||
// Return a measure of the sequences' similarity (float in [0,1]).
|
||||
//
|
||||
// Where T is the total number of elements in both sequences, and
|
||||
// M is the number of matches, this is 2.0*M / T.
|
||||
// Note that this is 1 if the sequences are identical, and 0 if
|
||||
// they have nothing in common.
|
||||
//
|
||||
// .Ratio() is expensive to compute if you haven't already computed
|
||||
// .GetMatchingBlocks() or .GetOpCodes(), in which case you may
|
||||
// want to try .QuickRatio() or .RealQuickRation() first to get an
|
||||
// upper bound.
|
||||
func (m *SequenceMatcher) Ratio() float64 {
|
||||
matches := 0
|
||||
for _, m := range m.GetMatchingBlocks() {
|
||||
matches += m.Size
|
||||
}
|
||||
return calculateRatio(matches, len(m.a)+len(m.b))
|
||||
}
|
||||
|
||||
// Return an upper bound on ratio() relatively quickly.
|
||||
//
|
||||
// This isn't defined beyond that it is an upper bound on .Ratio(), and
|
||||
// is faster to compute.
|
||||
func (m *SequenceMatcher) QuickRatio() float64 {
|
||||
// viewing a and b as multisets, set matches to the cardinality
|
||||
// of their intersection; this counts the number of matches
|
||||
// without regard to order, so is clearly an upper bound
|
||||
if m.fullBCount == nil {
|
||||
m.fullBCount = map[string]int{}
|
||||
for _, s := range m.b {
|
||||
m.fullBCount[s] = m.fullBCount[s] + 1
|
||||
}
|
||||
}
|
||||
|
||||
// avail[x] is the number of times x appears in 'b' less the
|
||||
// number of times we've seen it in 'a' so far ... kinda
|
||||
avail := map[string]int{}
|
||||
matches := 0
|
||||
for _, s := range m.a {
|
||||
n, ok := avail[s]
|
||||
if !ok {
|
||||
n = m.fullBCount[s]
|
||||
}
|
||||
avail[s] = n - 1
|
||||
if n > 0 {
|
||||
matches += 1
|
||||
}
|
||||
}
|
||||
return calculateRatio(matches, len(m.a)+len(m.b))
|
||||
}
|
||||
|
||||
// Return an upper bound on ratio() very quickly.
|
||||
//
|
||||
// This isn't defined beyond that it is an upper bound on .Ratio(), and
|
||||
// is faster to compute than either .Ratio() or .QuickRatio().
|
||||
func (m *SequenceMatcher) RealQuickRatio() float64 {
|
||||
la, lb := len(m.a), len(m.b)
|
||||
return calculateRatio(min(la, lb), la+lb)
|
||||
}
|
||||
|
||||
// Convert range to the "ed" format
|
||||
func formatRangeUnified(start, stop int) string {
|
||||
// Per the diff spec at http://www.unix.org/single_unix_specification/
|
||||
beginning := start + 1 // lines start numbering with one
|
||||
length := stop - start
|
||||
if length == 1 {
|
||||
return fmt.Sprintf("%d", beginning)
|
||||
}
|
||||
if length == 0 {
|
||||
beginning -= 1 // empty ranges begin at line just before the range
|
||||
}
|
||||
return fmt.Sprintf("%d,%d", beginning, length)
|
||||
}
|
||||
|
||||
// Unified diff parameters
|
||||
type UnifiedDiff struct {
|
||||
A []string // First sequence lines
|
||||
FromFile string // First file name
|
||||
FromDate string // First file time
|
||||
B []string // Second sequence lines
|
||||
ToFile string // Second file name
|
||||
ToDate string // Second file time
|
||||
Eol string // Headers end of line, defaults to LF
|
||||
Context int // Number of context lines
|
||||
}
|
||||
|
||||
// Compare two sequences of lines; generate the delta as a unified diff.
|
||||
//
|
||||
// Unified diffs are a compact way of showing line changes and a few
|
||||
// lines of context. The number of context lines is set by 'n' which
|
||||
// defaults to three.
|
||||
//
|
||||
// By default, the diff control lines (those with ---, +++, or @@) are
|
||||
// created with a trailing newline. This is helpful so that inputs
|
||||
// created from file.readlines() result in diffs that are suitable for
|
||||
// file.writelines() since both the inputs and outputs have trailing
|
||||
// newlines.
|
||||
//
|
||||
// For inputs that do not have trailing newlines, set the lineterm
|
||||
// argument to "" so that the output will be uniformly newline free.
|
||||
//
|
||||
// The unidiff format normally has a header for filenames and modification
|
||||
// times. Any or all of these may be specified using strings for
|
||||
// 'fromfile', 'tofile', 'fromfiledate', and 'tofiledate'.
|
||||
// The modification times are normally expressed in the ISO 8601 format.
|
||||
func WriteUnifiedDiff(writer io.Writer, diff UnifiedDiff) error {
|
||||
buf := bufio.NewWriter(writer)
|
||||
defer buf.Flush()
|
||||
wf := func(format string, args ...interface{}) error {
|
||||
_, err := buf.WriteString(fmt.Sprintf(format, args...))
|
||||
return err
|
||||
}
|
||||
ws := func(s string) error {
|
||||
_, err := buf.WriteString(s)
|
||||
return err
|
||||
}
|
||||
|
||||
if len(diff.Eol) == 0 {
|
||||
diff.Eol = "\n"
|
||||
}
|
||||
|
||||
started := false
|
||||
m := NewMatcher(diff.A, diff.B)
|
||||
for _, g := range m.GetGroupedOpCodes(diff.Context) {
|
||||
if !started {
|
||||
started = true
|
||||
fromDate := ""
|
||||
if len(diff.FromDate) > 0 {
|
||||
fromDate = "\t" + diff.FromDate
|
||||
}
|
||||
toDate := ""
|
||||
if len(diff.ToDate) > 0 {
|
||||
toDate = "\t" + diff.ToDate
|
||||
}
|
||||
if diff.FromFile != "" || diff.ToFile != "" {
|
||||
err := wf("--- %s%s%s", diff.FromFile, fromDate, diff.Eol)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
err = wf("+++ %s%s%s", diff.ToFile, toDate, diff.Eol)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
}
|
||||
}
|
||||
first, last := g[0], g[len(g)-1]
|
||||
range1 := formatRangeUnified(first.I1, last.I2)
|
||||
range2 := formatRangeUnified(first.J1, last.J2)
|
||||
if err := wf("@@ -%s +%s @@%s", range1, range2, diff.Eol); err != nil {
|
||||
return err
|
||||
}
|
||||
for _, c := range g {
|
||||
i1, i2, j1, j2 := c.I1, c.I2, c.J1, c.J2
|
||||
if c.Tag == 'e' {
|
||||
for _, line := range diff.A[i1:i2] {
|
||||
if err := ws(" " + line); err != nil {
|
||||
return err
|
||||
}
|
||||
}
|
||||
continue
|
||||
}
|
||||
if c.Tag == 'r' || c.Tag == 'd' {
|
||||
for _, line := range diff.A[i1:i2] {
|
||||
if err := ws("-" + line); err != nil {
|
||||
return err
|
||||
}
|
||||
}
|
||||
}
|
||||
if c.Tag == 'r' || c.Tag == 'i' {
|
||||
for _, line := range diff.B[j1:j2] {
|
||||
if err := ws("+" + line); err != nil {
|
||||
return err
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Like WriteUnifiedDiff but returns the diff a string.
|
||||
func GetUnifiedDiffString(diff UnifiedDiff) (string, error) {
|
||||
w := &bytes.Buffer{}
|
||||
err := WriteUnifiedDiff(w, diff)
|
||||
return string(w.Bytes()), err
|
||||
}
|
||||
|
||||
// Split a string on "\n" while preserving them. The output can be used
|
||||
// as input for UnifiedDiff and ContextDiff structures.
|
||||
func SplitLines(s string) []string {
|
||||
lines := strings.SplitAfter(s, "\n")
|
||||
lines[len(lines)-1] += "\n"
|
||||
return lines
|
||||
}
|
||||
|
|
@ -0,0 +1,266 @@
|
|||
// Copyright 2022 The Prometheus Authors
|
||||
// Licensed under the Apache License, Version 2.0 (the "License");
|
||||
// you may not use this file except in compliance with the License.
|
||||
// You may obtain a copy of the License at
|
||||
//
|
||||
// http://www.apache.org/licenses/LICENSE-2.0
|
||||
//
|
||||
// Unless required by applicable law or agreed to in writing, software
|
||||
// distributed under the License is distributed on an "AS IS" BASIS,
|
||||
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
// See the License for the specific language governing permissions and
|
||||
// limitations under the License.
|
||||
package internal
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"fmt"
|
||||
"math"
|
||||
"reflect"
|
||||
"strings"
|
||||
"testing"
|
||||
)
|
||||
|
||||
func assertAlmostEqual(t *testing.T, a, b float64, places int) {
|
||||
if math.Abs(a-b) > math.Pow10(-places) {
|
||||
t.Errorf("%.7f != %.7f", a, b)
|
||||
}
|
||||
}
|
||||
|
||||
func assertEqual(t *testing.T, a, b interface{}) {
|
||||
if !reflect.DeepEqual(a, b) {
|
||||
t.Errorf("%v != %v", a, b)
|
||||
}
|
||||
}
|
||||
|
||||
func splitChars(s string) []string {
|
||||
chars := make([]string, 0, len(s))
|
||||
// Assume ASCII inputs
|
||||
for i := 0; i != len(s); i++ {
|
||||
chars = append(chars, string(s[i]))
|
||||
}
|
||||
return chars
|
||||
}
|
||||
|
||||
func TestSequenceMatcherRatio(t *testing.T) {
|
||||
s := NewMatcher(splitChars("abcd"), splitChars("bcde"))
|
||||
assertEqual(t, s.Ratio(), 0.75)
|
||||
assertEqual(t, s.QuickRatio(), 0.75)
|
||||
assertEqual(t, s.RealQuickRatio(), 1.0)
|
||||
}
|
||||
|
||||
func TestGetOptCodes(t *testing.T) {
|
||||
a := "qabxcd"
|
||||
b := "abycdf"
|
||||
s := NewMatcher(splitChars(a), splitChars(b))
|
||||
w := &bytes.Buffer{}
|
||||
for _, op := range s.GetOpCodes() {
|
||||
fmt.Fprintf(w, "%s a[%d:%d], (%s) b[%d:%d] (%s)\n", string(op.Tag),
|
||||
op.I1, op.I2, a[op.I1:op.I2], op.J1, op.J2, b[op.J1:op.J2])
|
||||
}
|
||||
result := string(w.Bytes())
|
||||
expected := `d a[0:1], (q) b[0:0] ()
|
||||
e a[1:3], (ab) b[0:2] (ab)
|
||||
r a[3:4], (x) b[2:3] (y)
|
||||
e a[4:6], (cd) b[3:5] (cd)
|
||||
i a[6:6], () b[5:6] (f)
|
||||
`
|
||||
if expected != result {
|
||||
t.Errorf("unexpected op codes: \n%s", result)
|
||||
}
|
||||
}
|
||||
|
||||
func TestGroupedOpCodes(t *testing.T) {
|
||||
a := []string{}
|
||||
for i := 0; i != 39; i++ {
|
||||
a = append(a, fmt.Sprintf("%02d", i))
|
||||
}
|
||||
b := []string{}
|
||||
b = append(b, a[:8]...)
|
||||
b = append(b, " i")
|
||||
b = append(b, a[8:19]...)
|
||||
b = append(b, " x")
|
||||
b = append(b, a[20:22]...)
|
||||
b = append(b, a[27:34]...)
|
||||
b = append(b, " y")
|
||||
b = append(b, a[35:]...)
|
||||
s := NewMatcher(a, b)
|
||||
w := &bytes.Buffer{}
|
||||
for _, g := range s.GetGroupedOpCodes(-1) {
|
||||
fmt.Fprintf(w, "group\n")
|
||||
for _, op := range g {
|
||||
fmt.Fprintf(w, " %s, %d, %d, %d, %d\n", string(op.Tag),
|
||||
op.I1, op.I2, op.J1, op.J2)
|
||||
}
|
||||
}
|
||||
result := string(w.Bytes())
|
||||
expected := `group
|
||||
e, 5, 8, 5, 8
|
||||
i, 8, 8, 8, 9
|
||||
e, 8, 11, 9, 12
|
||||
group
|
||||
e, 16, 19, 17, 20
|
||||
r, 19, 20, 20, 21
|
||||
e, 20, 22, 21, 23
|
||||
d, 22, 27, 23, 23
|
||||
e, 27, 30, 23, 26
|
||||
group
|
||||
e, 31, 34, 27, 30
|
||||
r, 34, 35, 30, 31
|
||||
e, 35, 38, 31, 34
|
||||
`
|
||||
if expected != result {
|
||||
t.Errorf("unexpected op codes: \n%s", result)
|
||||
}
|
||||
}
|
||||
|
||||
func ExampleGetUnifiedDiffCode() {
|
||||
a := `one
|
||||
two
|
||||
three
|
||||
four
|
||||
fmt.Printf("%s,%T",a,b)`
|
||||
b := `zero
|
||||
one
|
||||
three
|
||||
four`
|
||||
diff := UnifiedDiff{
|
||||
A: SplitLines(a),
|
||||
B: SplitLines(b),
|
||||
FromFile: "Original",
|
||||
FromDate: "2005-01-26 23:30:50",
|
||||
ToFile: "Current",
|
||||
ToDate: "2010-04-02 10:20:52",
|
||||
Context: 3,
|
||||
}
|
||||
result, _ := GetUnifiedDiffString(diff)
|
||||
fmt.Println(strings.Replace(result, "\t", " ", -1))
|
||||
// Output:
|
||||
// --- Original 2005-01-26 23:30:50
|
||||
// +++ Current 2010-04-02 10:20:52
|
||||
// @@ -1,5 +1,4 @@
|
||||
// +zero
|
||||
// one
|
||||
// -two
|
||||
// three
|
||||
// four
|
||||
// -fmt.Printf("%s,%T",a,b)
|
||||
}
|
||||
|
||||
func rep(s string, count int) string {
|
||||
return strings.Repeat(s, count)
|
||||
}
|
||||
|
||||
func TestWithAsciiOneInsert(t *testing.T) {
|
||||
sm := NewMatcher(splitChars(rep("b", 100)),
|
||||
splitChars("a"+rep("b", 100)))
|
||||
assertAlmostEqual(t, sm.Ratio(), 0.995, 3)
|
||||
assertEqual(t, sm.GetOpCodes(),
|
||||
[]OpCode{{'i', 0, 0, 0, 1}, {'e', 0, 100, 1, 101}})
|
||||
assertEqual(t, len(sm.bPopular), 0)
|
||||
|
||||
sm = NewMatcher(splitChars(rep("b", 100)),
|
||||
splitChars(rep("b", 50)+"a"+rep("b", 50)))
|
||||
assertAlmostEqual(t, sm.Ratio(), 0.995, 3)
|
||||
assertEqual(t, sm.GetOpCodes(),
|
||||
[]OpCode{{'e', 0, 50, 0, 50}, {'i', 50, 50, 50, 51}, {'e', 50, 100, 51, 101}})
|
||||
assertEqual(t, len(sm.bPopular), 0)
|
||||
}
|
||||
|
||||
func TestWithAsciiOnDelete(t *testing.T) {
|
||||
sm := NewMatcher(splitChars(rep("a", 40)+"c"+rep("b", 40)),
|
||||
splitChars(rep("a", 40)+rep("b", 40)))
|
||||
assertAlmostEqual(t, sm.Ratio(), 0.994, 3)
|
||||
assertEqual(t, sm.GetOpCodes(),
|
||||
[]OpCode{{'e', 0, 40, 0, 40}, {'d', 40, 41, 40, 40}, {'e', 41, 81, 40, 80}})
|
||||
}
|
||||
|
||||
func TestWithAsciiBJunk(t *testing.T) {
|
||||
isJunk := func(s string) bool {
|
||||
return s == " "
|
||||
}
|
||||
sm := NewMatcherWithJunk(splitChars(rep("a", 40)+rep("b", 40)),
|
||||
splitChars(rep("a", 44)+rep("b", 40)), true, isJunk)
|
||||
assertEqual(t, sm.bJunk, map[string]struct{}{})
|
||||
|
||||
sm = NewMatcherWithJunk(splitChars(rep("a", 40)+rep("b", 40)),
|
||||
splitChars(rep("a", 44)+rep("b", 40)+rep(" ", 20)), false, isJunk)
|
||||
assertEqual(t, sm.bJunk, map[string]struct{}{" ": struct{}{}})
|
||||
|
||||
isJunk = func(s string) bool {
|
||||
return s == " " || s == "b"
|
||||
}
|
||||
sm = NewMatcherWithJunk(splitChars(rep("a", 40)+rep("b", 40)),
|
||||
splitChars(rep("a", 44)+rep("b", 40)+rep(" ", 20)), false, isJunk)
|
||||
assertEqual(t, sm.bJunk, map[string]struct{}{" ": struct{}{}, "b": struct{}{}})
|
||||
}
|
||||
|
||||
func TestSFBugsRatioForNullSeqn(t *testing.T) {
|
||||
sm := NewMatcher(nil, nil)
|
||||
assertEqual(t, sm.Ratio(), 1.0)
|
||||
assertEqual(t, sm.QuickRatio(), 1.0)
|
||||
assertEqual(t, sm.RealQuickRatio(), 1.0)
|
||||
}
|
||||
|
||||
func TestSFBugsComparingEmptyLists(t *testing.T) {
|
||||
groups := NewMatcher(nil, nil).GetGroupedOpCodes(-1)
|
||||
assertEqual(t, len(groups), 0)
|
||||
diff := UnifiedDiff{
|
||||
FromFile: "Original",
|
||||
ToFile: "Current",
|
||||
Context: 3,
|
||||
}
|
||||
result, err := GetUnifiedDiffString(diff)
|
||||
assertEqual(t, err, nil)
|
||||
assertEqual(t, result, "")
|
||||
}
|
||||
|
||||
func TestOutputFormatRangeFormatUnified(t *testing.T) {
|
||||
// Per the diff spec at http://www.unix.org/single_unix_specification/
|
||||
//
|
||||
// Each <range> field shall be of the form:
|
||||
// %1d", <beginning line number> if the range contains exactly one line,
|
||||
// and:
|
||||
// "%1d,%1d", <beginning line number>, <number of lines> otherwise.
|
||||
// If a range is empty, its beginning line number shall be the number of
|
||||
// the line just before the range, or 0 if the empty range starts the file.
|
||||
fm := formatRangeUnified
|
||||
assertEqual(t, fm(3, 3), "3,0")
|
||||
assertEqual(t, fm(3, 4), "4")
|
||||
assertEqual(t, fm(3, 5), "4,2")
|
||||
assertEqual(t, fm(3, 6), "4,3")
|
||||
assertEqual(t, fm(0, 0), "0,0")
|
||||
}
|
||||
|
||||
func TestSplitLines(t *testing.T) {
|
||||
allTests := []struct {
|
||||
input string
|
||||
want []string
|
||||
}{
|
||||
{"foo", []string{"foo\n"}},
|
||||
{"foo\nbar", []string{"foo\n", "bar\n"}},
|
||||
{"foo\nbar\n", []string{"foo\n", "bar\n", "\n"}},
|
||||
}
|
||||
for _, test := range allTests {
|
||||
assertEqual(t, SplitLines(test.input), test.want)
|
||||
}
|
||||
}
|
||||
|
||||
func benchmarkSplitLines(b *testing.B, count int) {
|
||||
str := strings.Repeat("foo\n", count)
|
||||
|
||||
b.ResetTimer()
|
||||
|
||||
n := 0
|
||||
for i := 0; i < b.N; i++ {
|
||||
n += len(SplitLines(str))
|
||||
}
|
||||
}
|
||||
|
||||
func BenchmarkSplitLines100(b *testing.B) {
|
||||
benchmarkSplitLines(b, 100)
|
||||
}
|
||||
|
||||
func BenchmarkSplitLines10000(b *testing.B) {
|
||||
benchmarkSplitLines(b, 10000)
|
||||
}
|
||||
|
|
@ -41,7 +41,9 @@ import (
|
|||
"bytes"
|
||||
"fmt"
|
||||
"io"
|
||||
"reflect"
|
||||
|
||||
"github.com/davecgh/go-spew/spew"
|
||||
"github.com/prometheus/common/expfmt"
|
||||
|
||||
dto "github.com/prometheus/client_model/go"
|
||||
|
|
@ -211,20 +213,73 @@ func compare(got, want []*dto.MetricFamily) error {
|
|||
return fmt.Errorf("encoding expected metrics failed: %s", err)
|
||||
}
|
||||
}
|
||||
|
||||
if wantBuf.String() != gotBuf.String() {
|
||||
return fmt.Errorf(`
|
||||
metric output does not match expectation; want:
|
||||
|
||||
%s
|
||||
got:
|
||||
|
||||
%s`, wantBuf.String(), gotBuf.String())
|
||||
|
||||
if diffErr := diff(wantBuf, gotBuf); diffErr != "" {
|
||||
return fmt.Errorf(diffErr)
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// diff returns a diff of both values as long as both are of the same type and
|
||||
// are a struct, map, slice, array or string. Otherwise it returns an empty string.
|
||||
func diff(expected interface{}, actual interface{}) string {
|
||||
if expected == nil || actual == nil {
|
||||
return ""
|
||||
}
|
||||
|
||||
et, ek := typeAndKind(expected)
|
||||
at, _ := typeAndKind(actual)
|
||||
if et != at {
|
||||
return ""
|
||||
}
|
||||
|
||||
if ek != reflect.Struct && ek != reflect.Map && ek != reflect.Slice && ek != reflect.Array && ek != reflect.String {
|
||||
return ""
|
||||
}
|
||||
|
||||
var e, a string
|
||||
c := spew.ConfigState{
|
||||
Indent: " ",
|
||||
DisablePointerAddresses: true,
|
||||
DisableCapacities: true,
|
||||
SortKeys: true,
|
||||
}
|
||||
if et != reflect.TypeOf("") {
|
||||
e = c.Sdump(expected)
|
||||
a = c.Sdump(actual)
|
||||
} else {
|
||||
e = reflect.ValueOf(expected).String()
|
||||
a = reflect.ValueOf(actual).String()
|
||||
}
|
||||
|
||||
diff, _ := internal.GetUnifiedDiffString(internal.UnifiedDiff{
|
||||
A: internal.SplitLines(e),
|
||||
B: internal.SplitLines(a),
|
||||
FromFile: "metric output does not match expectation; want",
|
||||
FromDate: "",
|
||||
ToFile: "got:",
|
||||
ToDate: "",
|
||||
Context: 1,
|
||||
})
|
||||
|
||||
if diff == "" {
|
||||
return ""
|
||||
}
|
||||
|
||||
return "\n\nDiff:\n" + diff
|
||||
}
|
||||
|
||||
// typeAndKind returns the type and kind of the given interface{}
|
||||
func typeAndKind(v interface{}) (reflect.Type, reflect.Kind) {
|
||||
t := reflect.TypeOf(v)
|
||||
k := t.Kind()
|
||||
|
||||
if k == reflect.Ptr {
|
||||
t = t.Elem()
|
||||
k = t.Kind()
|
||||
}
|
||||
return t, k
|
||||
}
|
||||
|
||||
func filterMetrics(metrics []*dto.MetricFamily, names []string) []*dto.MetricFamily {
|
||||
var filtered []*dto.MetricFamily
|
||||
for _, m := range metrics {
|
||||
|
|
|
|||
|
|
@ -284,17 +284,18 @@ func TestMetricNotFound(t *testing.T) {
|
|||
`
|
||||
|
||||
expectedError := `
|
||||
metric output does not match expectation; want:
|
||||
|
||||
# HELP some_other_metric A value that represents a counter.
|
||||
# TYPE some_other_metric counter
|
||||
some_other_metric{label1="value1"} 1
|
||||
|
||||
got:
|
||||
|
||||
# HELP some_total A value that represents a counter.
|
||||
# TYPE some_total counter
|
||||
some_total{label1="value1"} 1
|
||||
Diff:
|
||||
--- metric output does not match expectation; want
|
||||
+++ got:
|
||||
@@ -1,4 +1,4 @@
|
||||
-(bytes.Buffer) # HELP some_other_metric A value that represents a counter.
|
||||
-# TYPE some_other_metric counter
|
||||
-some_other_metric{label1="value1"} 1
|
||||
+(bytes.Buffer) # HELP some_total A value that represents a counter.
|
||||
+# TYPE some_total counter
|
||||
+some_total{label1="value1"} 1
|
||||
|
||||
`
|
||||
|
||||
err := CollectAndCompare(c, strings.NewReader(metadata+expected))
|
||||
|
|
|
|||
Loading…
Reference in New Issue