internal/gcimporter: run larger tests with and without aliases

Run larger and standard library tests both with and without the
gotypesaliases GODEBUG enabled. Skips two know failures on 1.22.

Fixes an incorrectly copied constant in an expectation.

Change-Id: I8054bf5609b7a0e6fb544bd906a00f2f02f75b31
Reviewed-on: https://go-review.googlesource.com/c/tools/+/616157
Reviewed-by: Alan Donovan <[email protected]>
Reviewed-by: Robert Findley <[email protected]>
Commit-Queue: Tim King <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>

Author: timothy-king

internal/gcimporter/gcimporter_test.go

@@ -120,6 +120,10 @@ func TestImportTestdata(t *testing.T) {
 	needsCompiler(t, "gc")
 	testenv.NeedsGoBuild(t) // to find stdlib export data in the build cache
 
+	testAliases(t, testImportTestdata)
+}
+
+func testImportTestdata(t *testing.T) {
 	tmpdir := mktmpdir(t)
 	defer os.RemoveAll(tmpdir)
 
@@ -168,9 +172,22 @@ func TestImportTypeparamTests(t *testing.T) {
 		t.Skipf("gc-built packages not available (compiler = %s)", runtime.Compiler)
 	}
 
+	testAliases(t, testImportTypeparamTests)
+}
+
+func testImportTypeparamTests(t *testing.T) {
 	tmpdir := mktmpdir(t)
 	defer os.RemoveAll(tmpdir)
 
+	// GoVersion -> GoDebug -> filename -> reason to skip
+	skips := map[int]map[string]map[string]string{
+		22: {aliasesOn: {
+			"issue50259.go": "internal compiler error: unexpected types2.Invalid",
+			"struct.go":     "badly formatted expectation E[int]",
+		}},
+	}
+	dbg, version := os.Getenv("GODEBUG"), testenv.Go1Point()
+
 	// Check go files in test/typeparam, except those that fail for a known
 	// reason.
 	rootDir := filepath.Join(runtime.GOROOT(), "test", "typeparam")
@@ -186,6 +203,11 @@ func TestImportTypeparamTests(t *testing.T) {
 		}
 
 		t.Run(entry.Name(), func(t *testing.T) {
+			if reason := skips[version][dbg][entry.Name()]; reason != "" {
+				t.Skipf("Skipping file %q with GODEBUG=%q due to %q at version 1.%d",
+					entry.Name(), dbg, reason, version)
+			}
+
 			filename := filepath.Join(rootDir, entry.Name())
 			src, err := os.ReadFile(filename)
 			if err != nil {
@@ -333,6 +355,10 @@ func TestImportStdLib(t *testing.T) {
 	needsCompiler(t, "gc")
 	testenv.NeedsGoBuild(t) // to find stdlib export data in the build cache
 
+	testAliases(t, testImportStdLib)
+}
+
+func testImportStdLib(t *testing.T) {
 	// Get list of packages in stdlib. Filter out test-only packages with {{if .GoFiles}} check.
 	var stderr bytes.Buffer
 	cmd := exec.Command("go", "list", "-f", "{{if .GoFiles}}{{.ImportPath}}{{end}}", "std")
@@ -1001,3 +1027,16 @@ const (
 	aliasesOff = "gotypesalias=0" // default GODEBUG in 1.22 (like x/tools)
 	aliasesOn  = "gotypesalias=1" // default after 1.23
 )
+
+// testAliases runs f within subtests with the GODEBUG gotypesalias enables and disabled.
+func testAliases(t *testing.T, f func(*testing.T)) {
+	for _, dbg := range []string{
+		aliasesOff,
+		aliasesOn,
+	} {
+		t.Run(dbg, func(t *testing.T) {
+			t.Setenv("GODEBUG", dbg)
+			f(t)
+		})
+	}
+}

internal/gcimporter/iexport_go118_test.go

@@ -99,6 +99,10 @@ func testExportSrc(t *testing.T, src []byte) {
 func TestIndexedImportTypeparamTests(t *testing.T) {
 	testenv.NeedsGoBuild(t) // to find stdlib export data in the build cache
 
+	testAliases(t, testIndexedImportTypeparamTests)
+}
+
+func testIndexedImportTypeparamTests(t *testing.T) {
 	// Check go files in test/typeparam.
 	rootDir := filepath.Join(runtime.GOROOT(), "test", "typeparam")
 	list, err := os.ReadDir(rootDir)

internal/gcimporter/iexport_test.go

@@ -47,6 +47,10 @@ func TestIExportData_stdlib(t *testing.T) {
 		t.Skip("skipping RAM hungry test in -short mode")
 	}
 
+	testAliases(t, testIExportData_stdlib)
+}
+
+func testIExportData_stdlib(t *testing.T) {
 	var errorsDir string // GOROOT/src/errors directory
 	{
 		cfg := packages.Config{
@@ -105,7 +109,7 @@ type UnknownType undefined
 	})
 
 	// Assert that we saw a plausible sized library.
-	const minStdlibPackages = 284
+	const minStdlibPackages = 248
 	if n := len(allPkgs); n < minStdlibPackages {
 		t.Errorf("Loaded only %d packages, want at least %d", n, minStdlibPackages)
 	}
@@ -225,6 +229,9 @@ func TestIExportData_long(t *testing.T) {
 }
 
 func TestIExportData_typealiases(t *testing.T) {
+	testAliases(t, testIExportData_typealiases)
+}
+func testIExportData_typealiases(t *testing.T) {
 	// parse and typecheck
 	fset1 := token.NewFileSet()
 	f, err := parser.ParseFile(fset1, "p.go", src, 0)

internal/gcimporter/shallow_test.go

@@ -27,6 +27,9 @@ func TestShallowStd(t *testing.T) {
 	}
 	testenv.NeedsTool(t, "go")
 
+	testAliases(t, testShallowStd)
+}
+func testShallowStd(t *testing.T) {
 	// Load import graph of the standard library.
 	// (No parsing or type-checking.)
 	cfg := &packages.Config{

internal/gcimporter/stdlib_test.go

@@ -19,10 +19,13 @@ import (
 )
 
 // TestStdlib ensures that all packages in std and x/tools can be
-// type-checked using export data. Takes around 3s.
+// type-checked using export data.
 func TestStdlib(t *testing.T) {
 	testenv.NeedsGoPackages(t)
 
+	testAliases(t, testStdlib)
+}
+func testStdlib(t *testing.T) {
 	// gcexportdata.Read rapidly consumes FileSet address space,
 	// so disable the test on 32-bit machines.
 	// (We could use a fresh FileSet per type-check, but that