go/ast: update (*File).Imports field in SortImports

Fixes #69694

Change-Id: I7884d42482f4f9d17e7d050d7c7730f20948169d
GitHub-Last-Rev: ecd6efabaa43cc87e31e94002febc9ed4273125a
GitHub-Pull-Request: golang/go#69695
Reviewed-on: https://go-review.googlesource.com/c/go/+/616340
Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Alan Donovan <adonovan@google.com>
Reviewed-by: Alan Donovan <adonovan@google.com>

diff --git a/src/go/ast/import.go b/src/go/ast/import.go
index 17f0db470f70a5ccd34e4535e3171b4b54543eb2..00f44ee3388aac5acb7d14627caca3dc1f1d6a8c 100644 (file)
--- a/src/go/ast/import.go
+++ b/src/go/ast/import.go
@@ -51,6 +51,16 @@ func SortImports(fset *token.FileSet, f *File) {
                        }
                }
        }
+
+       // Make File.Imports order consistent.
+       f.Imports = f.Imports[:0]
+       for _, decl := range f.Decls {
+               if decl, ok := decl.(*GenDecl); ok && decl.Tok == token.IMPORT {
+                       for _, spec := range decl.Specs {
+                               f.Imports = append(f.Imports, spec.(*ImportSpec))
+                       }
+               }
+       }
 }
 
 func lineAt(fset *token.FileSet, pos token.Pos) int {

diff --git a/src/go/ast/internal/tests/sortimports_test.go b/src/go/ast/internal/tests/sortimports_test.go
new file mode 100644 (file)
index 0000000..983de78
--- /dev/null
+++ b/src/go/ast/internal/tests/sortimports_test.go
@@ -0,0 +1,78 @@
+// Tests is a helper package to avoid cyclic dependency between go/ast and go/parser.
+package tests
+
+import (
+       "go/ast"
+       "go/parser"
+       "go/token"
+       "testing"
+)
+
+func TestSortImportsUpdatesFileImportsField(t *testing.T) {
+       t.Run("one import statement", func(t *testing.T) {
+               const src = `package test
+
+import (
+       "test"
+       "test" // test comment
+)
+`
+
+               fset := token.NewFileSet()
+               f, err := parser.ParseFile(fset, "test.go", src, parser.ParseComments|parser.SkipObjectResolution)
+               if err != nil {
+                       t.Fatal(err)
+               }
+
+               ast.SortImports(fset, f)
+
+               // Check that the duplicate import spec is eliminated.
+               importDeclSpecCount := len(f.Decls[0].(*ast.GenDecl).Specs)
+               if importDeclSpecCount != 1 {
+                       t.Fatalf("len(f.Decls[0].(*ast.GenDecl).Specs) = %v; want = 1", importDeclSpecCount)
+               }
+
+               // Check that File.Imports is consistent.
+               if len(f.Imports) != 1 {
+                       t.Fatalf("len(f.Imports) = %v; want = 1", len(f.Imports))
+               }
+       })
+
+       t.Run("multiple import statements", func(t *testing.T) {
+               const src = `package test
+
+import "unsafe"
+
+import (
+       "package"
+       "package"
+)
+
+import (
+       "test"
+       "test"
+)
+`
+
+               fset := token.NewFileSet()
+               f, err := parser.ParseFile(fset, "test.go", src, parser.ParseComments|parser.SkipObjectResolution)
+               if err != nil {
+                       t.Fatal(err)
+               }
+
+               ast.SortImports(fset, f)
+
+               // Check that three single-spec import decls remain.
+               for i := range 3 {
+                       importDeclSpecCount := len(f.Decls[i].(*ast.GenDecl).Specs)
+                       if importDeclSpecCount != 1 {
+                               t.Fatalf("len(f.Decls[%v].(*ast.GenDecl).Specs) = %v; want = 1", i, importDeclSpecCount)
+                       }
+               }
+
+               // Check that File.Imports is consistent.
+               if len(f.Imports) != 3 {
+                       t.Fatalf("len(f.Imports) = %v; want = 3", len(f.Imports))
+               }
+       })
+}