github.com/powerman/golang-tools@v0.1.11-0.20220410185822-5ad214d8d803/internal/typeparams/typeparams_test.go (about)

     1  // Copyright 2021 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  //go:build go1.18
     6  // +build go1.18
     7  
     8  package typeparams_test
     9  
    10  import (
    11  	"go/ast"
    12  	"go/importer"
    13  	"go/parser"
    14  	"go/token"
    15  	"go/types"
    16  	"strings"
    17  	"testing"
    18  
    19  	"github.com/powerman/golang-tools/internal/apidiff"
    20  	"github.com/powerman/golang-tools/internal/testenv"
    21  )
    22  
    23  func TestAPIConsistency(t *testing.T) {
    24  	testenv.NeedsGoBuild(t) // This is a lie. We actually need the source code.
    25  
    26  	// The packages below exclude enabled_*.go, as typeparams.Enabled is
    27  	// permitted to change between versions.
    28  	old := typeCheck(t, []string{"common.go", "typeparams_go117.go"})
    29  	new := typeCheck(t, []string{"common.go", "typeparams_go118.go"})
    30  
    31  	report := apidiff.Changes(old, new)
    32  
    33  	// Temporarily ignore API diff related to Environment, so that we can use a
    34  	// transient alias in go/types to allow renaming this type without ever
    35  	// breaking the x/tools builder.
    36  	// TODO(rfindley): remove this
    37  	var filteredChanges []apidiff.Change
    38  	for _, change := range report.Changes {
    39  		if strings.Contains(change.Message, "Environment") {
    40  			continue
    41  		}
    42  		filteredChanges = append(filteredChanges, change)
    43  	}
    44  	report.Changes = filteredChanges
    45  	if len(report.Changes) > 0 {
    46  		t.Errorf("API diff:\n%s", report)
    47  	}
    48  }
    49  
    50  func typeCheck(t *testing.T, filenames []string) *types.Package {
    51  	fset := token.NewFileSet()
    52  	var files []*ast.File
    53  	for _, name := range filenames {
    54  		f, err := parser.ParseFile(fset, name, nil, 0)
    55  		if err != nil {
    56  			t.Fatal(err)
    57  		}
    58  		files = append(files, f)
    59  	}
    60  	conf := types.Config{
    61  		Importer: importer.Default(),
    62  	}
    63  	pkg, err := conf.Check("", fset, files, nil)
    64  	if err != nil {
    65  		t.Fatal(err)
    66  	}
    67  	return pkg
    68  }