go/callgraph/cha: adds tests for (instantiated) generics
Updates golang/go#48525
Change-Id: Id568e0b188dd045356f556cb9d759a775c8c5a04
Reviewed-on: https://go-review.googlesource.com/c/tools/+/402474
Reviewed-by: Tim King <taking@google.com>
diff --git a/go/callgraph/cha/cha_test.go b/go/callgraph/cha/cha_test.go
index 8777ce4..a12b3d0 100644
--- a/go/callgraph/cha/cha_test.go
+++ b/go/callgraph/cha/cha_test.go
@@ -24,7 +24,9 @@
"golang.org/x/tools/go/callgraph"
"golang.org/x/tools/go/callgraph/cha"
"golang.org/x/tools/go/loader"
+ "golang.org/x/tools/go/ssa"
"golang.org/x/tools/go/ssa/ssautil"
+ "golang.org/x/tools/internal/typeparams"
)
var inputs = []string{
@@ -49,16 +51,7 @@
// the WANT comment at the end of the file.
func TestCHA(t *testing.T) {
for _, filename := range inputs {
- content, err := ioutil.ReadFile(filename)
- if err != nil {
- t.Errorf("couldn't read file '%s': %s", filename, err)
- continue
- }
-
- conf := loader.Config{
- ParserMode: parser.ParseComments,
- }
- f, err := conf.ParseFile(filename, content)
+ prog, f, mainPkg, err := loadProgInfo(filename, ssa.InstantiateGenerics)
if err != nil {
t.Error(err)
continue
@@ -66,34 +59,77 @@
want, pos := expectation(f)
if pos == token.NoPos {
- t.Errorf("No WANT: comment in %s", filename)
+ t.Error(fmt.Errorf("No WANT: comment in %s", filename))
continue
}
- conf.CreateFromFiles("main", f)
- iprog, err := conf.Load()
- if err != nil {
- t.Error(err)
- continue
- }
-
- prog := ssautil.CreateProgram(iprog, 0)
- mainPkg := prog.Package(iprog.Created[0].Pkg)
- prog.Build()
-
cg := cha.CallGraph(prog)
- if got := printGraph(cg, mainPkg.Pkg); got != want {
+ if got := printGraph(cg, mainPkg.Pkg, "dynamic", "Dynamic calls"); got != want {
t.Errorf("%s: got:\n%s\nwant:\n%s",
prog.Fset.Position(pos), got, want)
}
}
}
-func printGraph(cg *callgraph.Graph, from *types.Package) string {
+// TestCHAGenerics is TestCHA tailored for testing generics,
+func TestCHAGenerics(t *testing.T) {
+ if !typeparams.Enabled {
+ t.Skip("TestCHAGenerics requires type parameters")
+ }
+
+ filename := "testdata/generics.go"
+ prog, f, mainPkg, err := loadProgInfo(filename, ssa.InstantiateGenerics)
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ want, pos := expectation(f)
+ if pos == token.NoPos {
+ t.Fatal(fmt.Errorf("No WANT: comment in %s", filename))
+ }
+
+ cg := cha.CallGraph(prog)
+
+ if got := printGraph(cg, mainPkg.Pkg, "", "All calls"); got != want {
+ t.Errorf("%s: got:\n%s\nwant:\n%s",
+ prog.Fset.Position(pos), got, want)
+ }
+}
+
+func loadProgInfo(filename string, mode ssa.BuilderMode) (*ssa.Program, *ast.File, *ssa.Package, error) {
+ content, err := ioutil.ReadFile(filename)
+ if err != nil {
+ return nil, nil, nil, fmt.Errorf("couldn't read file '%s': %s", filename, err)
+ }
+
+ conf := loader.Config{
+ ParserMode: parser.ParseComments,
+ }
+ f, err := conf.ParseFile(filename, content)
+ if err != nil {
+ return nil, nil, nil, err
+ }
+
+ conf.CreateFromFiles("main", f)
+ iprog, err := conf.Load()
+ if err != nil {
+ return nil, nil, nil, err
+ }
+
+ prog := ssautil.CreateProgram(iprog, mode)
+ prog.Build()
+
+ return prog, f, prog.Package(iprog.Created[0].Pkg), nil
+}
+
+// printGraph returns a string representation of cg involving only edges
+// whose description contains edgeMatch. The string representation is
+// prefixed with a desc line.
+func printGraph(cg *callgraph.Graph, from *types.Package, edgeMatch string, desc string) string {
var edges []string
callgraph.GraphVisitEdges(cg, func(e *callgraph.Edge) error {
- if strings.Contains(e.Description(), "dynamic") {
+ if strings.Contains(e.Description(), edgeMatch) {
edges = append(edges, fmt.Sprintf("%s --> %s",
e.Caller.Func.RelString(from),
e.Callee.Func.RelString(from)))
@@ -103,7 +139,7 @@
sort.Strings(edges)
var buf bytes.Buffer
- buf.WriteString("Dynamic calls\n")
+ buf.WriteString(desc + "\n")
for _, edge := range edges {
fmt.Fprintf(&buf, " %s\n", edge)
}
diff --git a/go/callgraph/cha/testdata/generics.go b/go/callgraph/cha/testdata/generics.go
new file mode 100644
index 0000000..2711dc0
--- /dev/null
+++ b/go/callgraph/cha/testdata/generics.go
@@ -0,0 +1,45 @@
+//go:build ignore
+// +build ignore
+
+package main
+
+// Test of generic function calls.
+
+type I interface {
+ Foo()
+}
+
+type A struct{}
+
+func (a A) Foo() {}
+
+type B struct{}
+
+func (b B) Foo() {}
+
+func instantiated[X I](x X) {
+ x.Foo()
+}
+
+func Bar() {}
+
+func f(h func(), g func(I), k func(A), a A, b B) {
+ h()
+
+ k(a)
+ g(b) // g:func(I) is not matched by instantiated[[B]]:func(B)
+
+ instantiated[A](a) // static call
+ instantiated[B](b) // static call
+}
+
+// WANT:
+// All calls
+// (*A).Foo --> (A).Foo
+// (*B).Foo --> (B).Foo
+// f --> Bar
+// f --> instantiated[[main.A]]
+// f --> instantiated[[main.A]]
+// f --> instantiated[[main.B]]
+// instantiated[[main.A]] --> (A).Foo
+// instantiated[[main.B]] --> (B).Foo
