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
5package interp_test
6
7// This test runs the SSA interpreter over sample Go programs.
8// Because the interpreter requires intrinsics for assembly
9// functions and many low-level runtime routines, it is inherently
10// not robust to evolutionary change in the standard library.
11// Therefore the test cases are restricted to programs that
12// use a fake standard library in testdata/src containing a tiny
13// subset of simple functions useful for writing assertions.
14//
15// We no longer attempt to interpret any real standard packages such as
16// fmt or testing, as it proved too fragile.
17
18import (
19	"bytes"
20	"fmt"
21	"go/build"
22	"go/types"
23	"log"
24	"os"
25	"path/filepath"
26	"strings"
27	"testing"
28	"time"
29
30	"golang.org/x/tools/go/loader"
31	"golang.org/x/tools/go/ssa"
32	"golang.org/x/tools/go/ssa/interp"
33	"golang.org/x/tools/go/ssa/ssautil"
34)
35
36// Each line contains a space-separated list of $GOROOT/test/
37// filenames comprising the main package of a program.
38// They are ordered quickest-first, roughly.
39//
40// If a test in this list fails spuriously, remove it.
41var gorootTestTests = []string{
42	"235.go",
43	"alias1.go",
44	"func5.go",
45	"func6.go",
46	"func7.go",
47	"func8.go",
48	"helloworld.go",
49	"varinit.go",
50	"escape3.go",
51	"initcomma.go",
52	"cmp.go",
53	"compos.go",
54	"turing.go",
55	"indirect.go",
56	"complit.go",
57	"for.go",
58	"struct0.go",
59	"intcvt.go",
60	"printbig.go",
61	"deferprint.go",
62	"escape.go",
63	"range.go",
64	"const4.go",
65	"float_lit.go",
66	"bigalg.go",
67	"decl.go",
68	"if.go",
69	"named.go",
70	"bigmap.go",
71	"func.go",
72	"reorder2.go",
73	"gc.go",
74	"simassign.go",
75	"iota.go",
76	"nilptr2.go",
77	"utf.go",
78	"method.go",
79	"char_lit.go",
80	"env.go",
81	"int_lit.go",
82	"string_lit.go",
83	"defer.go",
84	"typeswitch.go",
85	"stringrange.go",
86	"reorder.go",
87	"method3.go",
88	"literal.go",
89	"nul1.go", // doesn't actually assert anything (errorcheckoutput)
90	"zerodivide.go",
91	"convert.go",
92	"convT2X.go",
93	"switch.go",
94	"ddd.go",
95	"blank.go", // partly disabled
96	"closedchan.go",
97	"divide.go",
98	"rename.go",
99	"nil.go",
100	"recover1.go",
101	"recover2.go",
102	"recover3.go",
103	"typeswitch1.go",
104	"floatcmp.go",
105	"crlf.go", // doesn't actually assert anything (runoutput)
106}
107
108// These are files in go.tools/go/ssa/interp/testdata/.
109var testdataTests = []string{
110	"boundmeth.go",
111	"complit.go",
112	"coverage.go",
113	"defer.go",
114	"fieldprom.go",
115	"ifaceconv.go",
116	"ifaceprom.go",
117	"initorder.go",
118	"methprom.go",
119	"mrvchain.go",
120	"range.go",
121	"recover.go",
122	"reflect.go",
123	"static.go",
124}
125
126func run(t *testing.T, input string) bool {
127	// The recover2 test case is broken on Go 1.14+. See golang/go#34089.
128	// TODO(matloob): Fix this.
129	if filepath.Base(input) == "recover2.go" {
130		t.Skip("The recover2.go test is broken in go1.14+. See golang.org/issue/34089.")
131	}
132
133	t.Logf("Input: %s\n", input)
134
135	start := time.Now()
136
137	ctx := build.Default    // copy
138	ctx.GOROOT = "testdata" // fake goroot
139	ctx.GOOS = "linux"
140	ctx.GOARCH = "amd64"
141
142	conf := loader.Config{Build: &ctx}
143	if _, err := conf.FromArgs([]string{input}, true); err != nil {
144		t.Errorf("FromArgs(%s) failed: %s", input, err)
145		return false
146	}
147
148	conf.Import("runtime")
149
150	// Print a helpful hint if we don't make it to the end.
151	var hint string
152	defer func() {
153		if hint != "" {
154			fmt.Println("FAIL")
155			fmt.Println(hint)
156		} else {
157			fmt.Println("PASS")
158		}
159
160		interp.CapturedOutput = nil
161	}()
162
163	hint = fmt.Sprintf("To dump SSA representation, run:\n%% go build golang.org/x/tools/cmd/ssadump && ./ssadump -test -build=CFP %s\n", input)
164
165	iprog, err := conf.Load()
166	if err != nil {
167		t.Errorf("conf.Load(%s) failed: %s", input, err)
168		return false
169	}
170
171	prog := ssautil.CreateProgram(iprog, ssa.SanityCheckFunctions)
172	prog.Build()
173
174	mainPkg := prog.Package(iprog.Created[0].Pkg)
175	if mainPkg == nil {
176		t.Fatalf("not a main package: %s", input)
177	}
178
179	interp.CapturedOutput = new(bytes.Buffer)
180
181	hint = fmt.Sprintf("To trace execution, run:\n%% go build golang.org/x/tools/cmd/ssadump && ./ssadump -build=C -test -run --interp=T %s\n", input)
182	exitCode := interp.Interpret(mainPkg, 0, &types.StdSizes{WordSize: 8, MaxAlign: 8}, input, []string{})
183	if exitCode != 0 {
184		t.Fatalf("interpreting %s: exit code was %d", input, exitCode)
185	}
186	// $GOROOT/test tests use this convention:
187	if strings.Contains(interp.CapturedOutput.String(), "BUG") {
188		t.Fatalf("interpreting %s: exited zero but output contained 'BUG'", input)
189	}
190
191	hint = "" // call off the hounds
192
193	if false {
194		t.Log(input, time.Since(start)) // test profiling
195	}
196
197	return true
198}
199
200func printFailures(failures []string) {
201	if failures != nil {
202		fmt.Println("The following tests failed:")
203		for _, f := range failures {
204			fmt.Printf("\t%s\n", f)
205		}
206	}
207}
208
209// TestTestdataFiles runs the interpreter on testdata/*.go.
210func TestTestdataFiles(t *testing.T) {
211	cwd, err := os.Getwd()
212	if err != nil {
213		log.Fatal(err)
214	}
215
216	var failures []string
217	for _, input := range testdataTests {
218		if !run(t, filepath.Join(cwd, "testdata", input)) {
219			failures = append(failures, input)
220		}
221	}
222	printFailures(failures)
223}
224
225// TestGorootTest runs the interpreter on $GOROOT/test/*.go.
226func TestGorootTest(t *testing.T) {
227	var failures []string
228
229	for _, input := range gorootTestTests {
230		if !run(t, filepath.Join(build.Default.GOROOT, "test", input)) {
231			failures = append(failures, input)
232		}
233	}
234	printFailures(failures)
235}
236