internal/analysisinternal: move FindBestMatch to internal/lsp/fuzzy

This is used by internal/lsp/analysis/fillreturns and
internal/lsp/analysis/fillstruct. This doesn't need to be in this
analysisinternal package.

This removes the dependency path

  go/analysis/internal/checker ->
    internal/analysisinternal ->
      internal/lsp/fuzzy

Change-Id: I5db674ca30eb06ae6ce7021397cf5530a695af4e
Reviewed-on: https://go-review.googlesource.com/c/tools/+/417418
gopls-CI: kokoro <noreply+kokoro@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Robert Findley <rfindley@google.com>
Run-TryBot: Hyang-Ah Hana Kim <hyangah@gmail.com>

internal/analysisinternal/analysis.go

@@ -12,8 +12,6 @@ import (
 	"go/token"
 	"go/types"
 	"strconv"
-
-	"golang.org/x/tools/internal/lsp/fuzzy"
 )
 
 // Flag to gate diagnostics for fuzz tests in 1.18.
@@ -397,30 +395,3 @@ func equivalentTypes(want, got types.Type) bool {
 	}
 	return types.AssignableTo(want, got)
 }
-
-// FindBestMatch employs fuzzy matching to evaluate the similarity of each given identifier to the
-// given pattern. We return the identifier whose name is most similar to the pattern.
-func FindBestMatch(pattern string, idents []*ast.Ident) ast.Expr {
-	fuzz := fuzzy.NewMatcher(pattern)
-	var bestFuzz ast.Expr
-	highScore := float32(0) // minimum score is 0 (no match)
-	for _, ident := range idents {
-		// TODO: Improve scoring algorithm.
-		score := fuzz.Score(ident.Name)
-		if score > highScore {
-			highScore = score
-			bestFuzz = ident
-		} else if score == 0 {
-			// Order matters in the fuzzy matching algorithm. If we find no match
-			// when matching the target to the identifier, try matching the identifier
-			// to the target.
-			revFuzz := fuzzy.NewMatcher(ident.Name)
-			revScore := revFuzz.Score(pattern)
-			if revScore > highScore {
-				highScore = revScore
-				bestFuzz = ident
-			}
-		}
-	}
-	return bestFuzz
-}

internal/lsp/analysis/fillreturns/fillreturns.go

@@ -19,6 +19,7 @@ import (
 	"golang.org/x/tools/go/analysis"
 	"golang.org/x/tools/go/ast/astutil"
 	"golang.org/x/tools/internal/analysisinternal"
+	"golang.org/x/tools/internal/lsp/fuzzy"
 	"golang.org/x/tools/internal/typeparams"
 )
 
@@ -191,7 +192,7 @@ outer:
 				// Find the identifier whose name is most similar to the return type.
 				// If we do not find any identifier that matches the pattern,
 				// generate a zero value.
-				value := analysisinternal.FindBestMatch(retTyp.String(), idents)
+				value := fuzzy.FindBestMatch(retTyp.String(), idents)
 				if value == nil {
 					value = analysisinternal.ZeroValue(file, pass.Pkg, retTyp)
 				}

internal/lsp/analysis/fillstruct/fillstruct.go

@@ -21,6 +21,7 @@ import (
 	"golang.org/x/tools/go/ast/astutil"
 	"golang.org/x/tools/go/ast/inspector"
 	"golang.org/x/tools/internal/analysisinternal"
+	"golang.org/x/tools/internal/lsp/fuzzy"
 	"golang.org/x/tools/internal/span"
 	"golang.org/x/tools/internal/typeparams"
 )
@@ -254,7 +255,7 @@ func SuggestedFix(fset *token.FileSet, rng span.Range, content []byte, file *ast
 			// Find the identifier whose name is most similar to the name of the field's key.
 			// If we do not find any identifier that matches the pattern, generate a new value.
 			// NOTE: We currently match on the name of the field key rather than the field type.
-			value := analysisinternal.FindBestMatch(obj.Field(i).Name(), idents)
+			value := fuzzy.FindBestMatch(obj.Field(i).Name(), idents)
 			if value == nil {
 				value = populateValue(file, pkg, fieldTyp)
 			}

internal/lsp/fuzzy/matcher.go

@@ -8,6 +8,7 @@ package fuzzy
 import (
 	"bytes"
 	"fmt"
+	"go/ast"
 )
 
 const (
@@ -405,3 +406,30 @@ func (m *Matcher) poorMatch() bool {
 	}
 	return false
 }
+
+// FindBestMatch employs fuzzy matching to evaluate the similarity of each given identifier to the
+// given pattern. We return the identifier whose name is most similar to the pattern.
+func FindBestMatch(pattern string, idents []*ast.Ident) ast.Expr {
+	fuzz := NewMatcher(pattern)
+	var bestFuzz ast.Expr
+	highScore := float32(0) // minimum score is 0 (no match)
+	for _, ident := range idents {
+		// TODO: Improve scoring algorithm.
+		score := fuzz.Score(ident.Name)
+		if score > highScore {
+			highScore = score
+			bestFuzz = ident
+		} else if score == 0 {
+			// Order matters in the fuzzy matching algorithm. If we find no match
+			// when matching the target to the identifier, try matching the identifier
+			// to the target.
+			revFuzz := NewMatcher(ident.Name)
+			revScore := revFuzz.Score(pattern)
+			if revScore > highScore {
+				highScore = revScore
+				bestFuzz = ident
+			}
+		}
+	}
+	return bestFuzz
+}