internal/lsp/source: return location(s) for imported packages

Fixes golang/go#32993

Change-Id: Iff2f7ab8e34eea1ce7c1ab99fb2e51589dce95c4
Reviewed-on: https://go-review.googlesource.com/c/tools/+/210321
Run-TryBot: Rebecca Stambler <rstambler@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rebecca Stambler <rstambler@golang.org>

internal/lsp/definition.go

@@ -20,16 +20,21 @@ func (s *Server) definition(ctx context.Context, params *protocol.DefinitionPara
 	if err != nil {
 		return nil, err
 	}
-	decRange, err := ident.Declaration.Range()
-	if err != nil {
-		return nil, err
-	}
-	return []protocol.Location{
-		{
-			URI:   protocol.URIFromSpanURI(ident.Declaration.URI()),
+
+	var locations []protocol.Location
+	for _, ref := range ident.Declaration.MappedRange {
+		decRange, err := ref.Range()
+		if err != nil {
+			return nil, err
+		}
+
+		locations = append(locations, protocol.Location{
+			URI:   protocol.URIFromSpanURI(ref.URI()),
 			Range: decRange,
-		},
-	}, nil
+		})
+	}
+
+	return locations, nil
 }
 
 func (s *Server) typeDefinition(ctx context.Context, params *protocol.TypeDefinitionParams) ([]protocol.Location, error) {

internal/lsp/source/hover.go

@@ -119,7 +119,7 @@ func (i *IdentifierInfo) linkAndSymbolName() (string, string) {
 	// package's API). This is true if the request originated in a test package,
 	// and if the declaration is also found in the same test package.
 	if i.pkg != nil && obj.Pkg() != nil && i.pkg.ForTest() != "" {
-		if _, pkg, _ := FindFileInPackage(i.pkg, i.Declaration.URI()); i.pkg == pkg {
+		if _, pkg, _ := FindFileInPackage(i.pkg, i.Declaration.MappedRange[0].URI()); i.pkg == pkg {
 			return "", ""
 		}
 	}

internal/lsp/source/identifier.go

@@ -41,9 +41,9 @@ type IdentifierInfo struct {
 }
 
 type Declaration struct {
-	mappedRange
-	node ast.Node
-	obj  types.Object
+	MappedRange []mappedRange
+	node        ast.Node
+	obj         types.Object
 }
 
 // Identifier returns identifier information for a position
@@ -111,6 +111,7 @@ func findIdentifier(ctx context.Context, s Snapshot, pkg Package, file *ast.File
 	if result.mappedRange, err = posToMappedRange(view, pkg, result.ident.Pos(), result.ident.End()); err != nil {
 		return nil, err
 	}
+
 	result.Declaration.obj = pkg.GetTypesInfo().ObjectOf(result.ident)
 	if result.Declaration.obj == nil {
 		// If there was no types.Object for the declaration, there might be an implicit local variable
@@ -138,9 +139,13 @@ func findIdentifier(ctx context.Context, s Snapshot, pkg Package, file *ast.File
 			return nil, errors.Errorf("no declaration for %s", result.Name)
 		}
 		result.Declaration.node = decl
-		if result.Declaration.mappedRange, err = nameToMappedRange(view, pkg, decl.Pos(), result.Name); err != nil {
+
+		rng, err := nameToMappedRange(view, pkg, decl.Pos(), result.Name)
+		if err != nil {
 			return nil, err
 		}
+		result.Declaration.MappedRange = append(result.Declaration.MappedRange, rng)
+
 		return result, nil
 	}
 
@@ -154,9 +159,12 @@ func findIdentifier(ctx context.Context, s Snapshot, pkg Package, file *ast.File
 		}
 	}
 
-	if result.Declaration.mappedRange, err = objToMappedRange(view, pkg, result.Declaration.obj); err != nil {
+	rng, err := objToMappedRange(view, pkg, result.Declaration.obj)
+	if err != nil {
 		return nil, err
 	}
+	result.Declaration.MappedRange = append(result.Declaration.MappedRange, rng)
+
 	if result.Declaration.node, err = objToNode(s.View(), pkg, result.Declaration.obj); err != nil {
 		return nil, err
 	}
@@ -273,19 +281,20 @@ func importSpec(s Snapshot, pkg Package, file *ast.File, pos token.Pos) (*Identi
 	if importedPkg.GetSyntax() == nil {
 		return nil, errors.Errorf("no syntax for for %q", importPath)
 	}
-	// Heuristic: Jump to the longest (most "interesting") file of the package.
-	var dest *ast.File
-	for _, f := range importedPkg.GetSyntax() {
-		if dest == nil || f.End()-f.Pos() > dest.End()-dest.Pos() {
-			dest = f
-		}
-	}
-	if dest == nil {
+	// Return all of the files in the package as the definition of the import spec.
+	dest := pkg.GetSyntax()
+	if len(dest) == 0 {
 		return nil, errors.Errorf("package %q has no files", importPath)
 	}
-	if result.Declaration.mappedRange, err = posToMappedRange(s.View(), pkg, dest.Pos(), dest.End()); err != nil {
-		return nil, err
+
+	for _, dst := range importedPkg.GetSyntax() {
+		rng, err := posToMappedRange(s.View(), pkg, dst.Pos(), dst.End())
+		if err != nil {
+			return nil, err
+		}
+		result.Declaration.MappedRange = append(result.Declaration.MappedRange, rng)
 	}
+
 	result.Declaration.node = imp
 	return result, nil
 }

internal/lsp/source/signature_help.go

@@ -109,10 +109,10 @@ FindCall:
 			return nil, 0, err
 		}
 		decl := &Declaration{
-			obj:         obj,
-			mappedRange: rng,
-			node:        node,
+			obj:  obj,
+			node: node,
 		}
+		decl.MappedRange = append(decl.MappedRange, rng)
 		d, err := decl.hover(ctx)
 		if err != nil {
 			return nil, 0, err

internal/lsp/source/source_test.go

@@ -490,7 +490,7 @@ func (r *runner) Definition(t *testing.T, spn span.Span, d tests.Definition) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	rng, err := ident.Declaration.Range()
+	rng, err := ident.Declaration.MappedRange[0].Range()
 	if err != nil {
 		t.Fatal(err)
 	}