internal/lsp: permit renaming symbols declared in other packages

Also, add a test for it.

Fixes golang/go#36743

Change-Id: I750ea36189a4ec5c9dc8553e4739b0238c2b29c8
Reviewed-on: https://go-review.googlesource.com/c/tools/+/216306
Run-TryBot: Rebecca Stambler <[email protected]>
TryBot-Result: Gobot Gobot <[email protected]>
Reviewed-by: Heschi Kreinick <[email protected]>

Author: stamblerre

internal/lsp/source/rename.go

@@ -88,7 +88,6 @@ func Rename(ctx context.Context, s Snapshot, f FileHandle, pp protocol.Position,
 
 	obj := qos[0].obj
 	pkg := qos[0].pkg
-	sourcePkg := qos[0].sourcePkg
 
 	if obj.Name() == newName {
 		return nil, errors.Errorf("old and new names are the same: %s", newName)
@@ -103,10 +102,6 @@ func Rename(ctx context.Context, s Snapshot, f FileHandle, pp protocol.Position,
 	if pkg == nil || pkg.IsIllTyped() {
 		return nil, errors.Errorf("package for %s is ill typed", f.Identity().URI)
 	}
-	// Do not rename identifiers declared in another package.
-	if pkg != sourcePkg {
-		return nil, errors.Errorf("rename failed because %q is declared in a different package (%s)", obj.Name(), pkg.PkgPath())
-	}
 
 	refs, err := References(ctx, s, f, pp, true)
 	if err != nil {

internal/lsp/testdata/rename/crosspkg/crosspkg.go.golden

@@ -15,7 +15,7 @@ import "golang.org/x/tools/internal/lsp/rename/crosspkg"
 
 func Other() {
 	crosspkg.Bar
-	crosspkg.Dolphin()
+	crosspkg.Dolphin() //@rename("Foo", "Flamingo")
 }
 
 -- Tomato-rename --
@@ -35,6 +35,6 @@ import "golang.org/x/tools/internal/lsp/rename/crosspkg"
 
 func Other() {
 	crosspkg.Tomato
-	crosspkg.Foo()
+	crosspkg.Foo() //@rename("Foo", "Flamingo")
 }
 

internal/lsp/testdata/rename/crosspkg/other/other.go

@@ -4,5 +4,5 @@ import "golang.org/x/tools/internal/lsp/rename/crosspkg"
 
 func Other() {
 	crosspkg.Bar
-	crosspkg.Foo()
+	crosspkg.Foo() //@rename("Foo", "Flamingo")
 }

internal/lsp/testdata/rename/crosspkg/other/other.go.golden

@@ -0,0 +1,20 @@
+-- Flamingo-rename --
+crosspkg.go:
+package crosspkg
+
+func Flamingo() { //@rename("Foo", "Dolphin")
+
+}
+
+var Bar int //@rename("Bar", "Tomato")
+
+other.go:
+package other
+
+import "golang.org/x/tools/internal/lsp/rename/crosspkg"
+
+func Other() {
+	crosspkg.Bar
+	crosspkg.Flamingo() //@rename("Foo", "Flamingo")
+}
+

internal/lsp/testdata/summary.txt.golden

@@ -15,7 +15,7 @@ DefinitionsCount = 43
 TypeDefinitionsCount = 2
 HighlightsCount = 52
 ReferencesCount = 8
-RenamesCount = 22
+RenamesCount = 23
 PrepareRenamesCount = 8
 SymbolsCount = 1
 SignaturesCount = 22