// Simplifying wrapper around buildutil.FakeContext for single-file packages.
func fakeContext(pkgs map[string]string) *build.Context {
pkgs2 := make(map[string]map[string]string)
for path, content := range pkgs {
pkgs2[path] = map[string]string{"x.go": content}
}
return buildutil.FakeContext(pkgs2)
}
func TestCycles(t *testing.T) {
for _, test := range []struct {
descr string
ctxt *build.Context
wantErr string
}{
{
"self-cycle",
fakeContext(map[string]string{
"main": `package main; import _ "selfcycle"`,
"selfcycle": `package selfcycle; import _ "selfcycle"`,
}),
`import cycle: selfcycle -> selfcycle`,
},
{
"three-package cycle",
fakeContext(map[string]string{
"main": `package main; import _ "a"`,
"a": `package a; import _ "b"`,
"b": `package b; import _ "c"`,
"c": `package c; import _ "a"`,
}),
`import cycle: c -> a -> b -> c`,
},
{
"self-cycle in dependency of test file",
buildutil.FakeContext(map[string]map[string]string{
"main": {
"main.go": `package main`,
"main_test.go": `package main; import _ "a"`,
},
"a": {
"a.go": `package a; import _ "a"`,
},
}),
`import cycle: a -> a`,
},
// TODO(adonovan): fix: these fail
// {
// "two-package cycle in dependency of test file",
// buildutil.FakeContext(map[string]map[string]string{
// "main": {
// "main.go": `package main`,
// "main_test.go": `package main; import _ "a"`,
// },
// "a": {
// "a.go": `package a; import _ "main"`,
// },
// }),
// `import cycle: main -> a -> main`,
// },
// {
// "self-cycle in augmented package",
// buildutil.FakeContext(map[string]map[string]string{
// "main": {
// "main.go": `package main`,
// "main_test.go": `package main; import _ "main"`,
// },
// }),
// `import cycle: main -> main`,
// },
} {
conf := loader.Config{
AllowErrors: true,
Build: test.ctxt,
}
var mu sync.Mutex
var allErrors []error
conf.TypeChecker.Error = func(err error) {
mu.Lock()
allErrors = append(allErrors, err)
mu.Unlock()
}
conf.ImportWithTests("main")
prog, err := conf.Load()
if err != nil {
t.Errorf("%s: Load failed: %s", test.descr, err)
}
if prog == nil {
t.Fatalf("%s: Load returned nil *Program", test.descr)
}
if !hasError(allErrors, test.wantErr) {
t.Errorf("%s: Load() errors = %q, want %q",
test.descr, allErrors, test.wantErr)
}
}
// TODO(adonovan):
// - Test that in a legal test cycle, none of the symbols
// defined by augmentation are visible via import.
}