github.com/powerman/golang-tools@v0.1.11-0.20220410185822-5ad214d8d803/go/ssa/ssautil/switch_test.go (about)

     1  // Copyright 2013 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  // No testdata on Android.
     6  
     7  //go:build !android
     8  // +build !android
     9  
    10  package ssautil_test
    11  
    12  import (
    13  	"go/parser"
    14  	"strings"
    15  	"testing"
    16  
    17  	"github.com/powerman/golang-tools/go/loader"
    18  	"github.com/powerman/golang-tools/go/ssa"
    19  	"github.com/powerman/golang-tools/go/ssa/ssautil"
    20  )
    21  
    22  func TestSwitches(t *testing.T) {
    23  	conf := loader.Config{ParserMode: parser.ParseComments}
    24  	f, err := conf.ParseFile("testdata/switches.go", nil)
    25  	if err != nil {
    26  		t.Error(err)
    27  		return
    28  	}
    29  
    30  	conf.CreateFromFiles("main", f)
    31  	iprog, err := conf.Load()
    32  	if err != nil {
    33  		t.Error(err)
    34  		return
    35  	}
    36  
    37  	prog := ssautil.CreateProgram(iprog, 0)
    38  	mainPkg := prog.Package(iprog.Created[0].Pkg)
    39  	mainPkg.Build()
    40  
    41  	for _, mem := range mainPkg.Members {
    42  		if fn, ok := mem.(*ssa.Function); ok {
    43  			if fn.Synthetic != "" {
    44  				continue // e.g. init()
    45  			}
    46  			// Each (multi-line) "switch" comment within
    47  			// this function must match the printed form
    48  			// of a ConstSwitch.
    49  			var wantSwitches []string
    50  			for _, c := range f.Comments {
    51  				if fn.Syntax().Pos() <= c.Pos() && c.Pos() < fn.Syntax().End() {
    52  					text := strings.TrimSpace(c.Text())
    53  					if strings.HasPrefix(text, "switch ") {
    54  						wantSwitches = append(wantSwitches, text)
    55  					}
    56  				}
    57  			}
    58  
    59  			switches := ssautil.Switches(fn)
    60  			if len(switches) != len(wantSwitches) {
    61  				t.Errorf("in %s, found %d switches, want %d", fn, len(switches), len(wantSwitches))
    62  			}
    63  			for i, sw := range switches {
    64  				got := sw.String()
    65  				if i >= len(wantSwitches) {
    66  					continue
    67  				}
    68  				want := wantSwitches[i]
    69  				if got != want {
    70  					t.Errorf("in %s, found switch %d: got <<%s>>, want <<%s>>", fn, i, got, want)
    71  				}
    72  			}
    73  		}
    74  	}
    75  }