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// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build go1.5
package ssa
// CreateTestMainPackage synthesizes a main package that runs all the
// tests of the supplied packages.
// It is closely coupled to $GOROOT/src/cmd/go/test.go and $GOROOT/src/testing.
import (
"go/ast"
exact "go/constant"
"go/token"
"go/types"
"os"
"sort"
"strings"
)
// FindTests returns the list of packages that define at least one Test,
// Example or Benchmark function (as defined by "go test"), and the
// lists of all such functions.
//
func FindTests(pkgs []*Package) (testpkgs []*Package, tests, benchmarks, examples []*Function) {
if len(pkgs) == 0 {
return
}
prog := pkgs[0].Prog
// The first two of these may be nil: if the program doesn't import "testing",
// it can't contain any tests, but it may yet contain Examples.
var testSig *types.Signature // func(*testing.T)
var benchmarkSig *types.Signature // func(*testing.B)
var exampleSig = types.NewSignature(nil, nil, nil, false) // func()
// Obtain the types from the parameters of testing.Main().
if testingPkg := prog.ImportedPackage("testing"); testingPkg != nil {
params := testingPkg.Func("Main").Signature.Params()
testSig = funcField(params.At(1).Type())
benchmarkSig = funcField(params.At(2).Type())
}
seen := make(map[*Package]bool)
for _, pkg := range pkgs {
if pkg.Prog != prog {
panic("wrong Program")
}
// TODO(adonovan): use a stable order, e.g. lexical.
for _, mem := range pkg.Members {
if f, ok := mem.(*Function); ok &&
ast.IsExported(f.Name()) &&
strings.HasSuffix(prog.Fset.Position(f.Pos()).Filename, "_test.go") {
switch {
case testSig != nil && isTestSig(f, "Test", testSig):
tests = append(tests, f)
case benchmarkSig != nil && isTestSig(f, "Benchmark", benchmarkSig):
benchmarks = append(benchmarks, f)
case isTestSig(f, "Example", exampleSig):
examples = append(examples, f)
default:
continue
}
if !seen[pkg] {
seen[pkg] = true
testpkgs = append(testpkgs, pkg)
}
}
}
}
return
}
// Like isTest, but checks the signature too.
func isTestSig(f *Function, prefix string, sig *types.Signature) bool {
return isTest(f.Name(), prefix) && types.Identical(f.Signature, sig)
}
// If non-nil, testMainStartBodyHook is called immediately after
// startBody for main.init and main.main, making it easy for users to
// add custom imports and initialization steps for proprietary build
// systems that don't exactly follow 'go test' conventions.
var testMainStartBodyHook func(*Function)
// CreateTestMainPackage creates and returns a synthetic "main"
// package that runs all the tests of the supplied packages, similar
// to the one that would be created by the 'go test' tool.
//
// It returns nil if the program contains no tests.
//
func (prog *Program) CreateTestMainPackage(pkgs ...*Package) *Package {
pkgs, tests, benchmarks, examples := FindTests(pkgs)
if len(pkgs) == 0 {
return nil
}
testmain := &Package{
Prog: prog,
Members: make(map[string]Member),
values: make(map[types.Object]Value),
Pkg: types.NewPackage("test$main", "main"),
}
// Build package's init function.
init := &Function{
name: "init",
Signature: new(types.Signature),
Synthetic: "package initializer",
Pkg: testmain,
Prog: prog,
}
init.startBody()
if testMainStartBodyHook != nil {
testMainStartBodyHook(init)
}
// Initialize packages to test.
var pkgpaths []string
for _, pkg := range pkgs {
var v Call
v.Call.Value = pkg.init
v.setType(types.NewTuple())
init.emit(&v)
pkgpaths = append(pkgpaths, pkg.Pkg.Path())
}
sort.Strings(pkgpaths)
init.emit(new(Return))
init.finishBody()
testmain.init = init
testmain.Pkg.MarkComplete()
testmain.Members[init.name] = init
// For debugging convenience, define an unexported const
// that enumerates the packages.
packagesConst := types.NewConst(token.NoPos, testmain.Pkg, "packages", tString,
exact.MakeString(strings.Join(pkgpaths, " ")))
memberFromObject(testmain, packagesConst, nil)
// Create main *types.Func and *ssa.Function
mainFunc := types.NewFunc(token.NoPos, testmain.Pkg, "main", new(types.Signature))
memberFromObject(testmain, mainFunc, nil)
main := testmain.Func("main")
main.Synthetic = "test main function"
main.startBody()
if testMainStartBodyHook != nil {
testMainStartBodyHook(main)
}
if testingPkg := prog.ImportedPackage("testing"); testingPkg != nil {
testingMain := testingPkg.Func("Main")
testingMainParams := testingMain.Signature.Params()
// The generated code is as if compiled from this:
//
// func main() {
// match := func(_, _ string) (bool, error) { return true, nil }
// tests := []testing.InternalTest{{"TestFoo", TestFoo}, ...}
// benchmarks := []testing.InternalBenchmark{...}
// examples := []testing.InternalExample{...}
// testing.Main(match, tests, benchmarks, examples)
// }
matcher := &Function{
name: "matcher",
Signature: testingMainParams.At(0).Type().(*types.Signature),
Synthetic: "test matcher predicate",
parent: main,
Pkg: testmain,
Prog: prog,
}
main.AnonFuncs = append(main.AnonFuncs, matcher)
matcher.startBody()
matcher.emit(&Return{Results: []Value{vTrue, nilConst(types.Universe.Lookup("error").Type())}})
matcher.finishBody()
// Emit call: testing.Main(matcher, tests, benchmarks, examples).
var c Call
c.Call.Value = testingMain
c.Call.Args = []Value{
matcher,
testMainSlice(main, tests, testingMainParams.At(1).Type()),
testMainSlice(main, benchmarks, testingMainParams.At(2).Type()),
testMainSlice(main, examples, testingMainParams.At(3).Type()),
}
emitTailCall(main, &c)
} else {
// The program does not import "testing", but FindTests
// returned non-nil, which must mean there were Examples
// but no Tests or Benchmarks.
// We'll simply call them from testmain.main; this will
// ensure they don't panic, but will not check any
// "Output:" comments.
for _, eg := range examples {
var c Call
c.Call.Value = eg
c.setType(types.NewTuple())
main.emit(&c)
}
main.emit(&Return{})
main.currentBlock = nil
}
main.finishBody()
testmain.Members["main"] = main
if prog.mode&PrintPackages != 0 {
printMu.Lock()
testmain.WriteTo(os.Stdout)
printMu.Unlock()
}
if prog.mode&SanityCheckFunctions != 0 {
sanityCheckPackage(testmain)
}
prog.packages[testmain.Pkg] = testmain
return testmain
}
// testMainSlice emits to fn code to construct a slice of type slice
// (one of []testing.Internal{Test,Benchmark,Example}) for all
// functions in testfuncs. It returns the slice value.
//
func testMainSlice(fn *Function, testfuncs []*Function, slice types.Type) Value {
if testfuncs == nil {
return nilConst(slice)
}
tElem := slice.(*types.Slice).Elem()
tPtrString := types.NewPointer(tString)
tPtrElem := types.NewPointer(tElem)
tPtrFunc := types.NewPointer(funcField(slice))
// TODO(adonovan): fix: populate the
// testing.InternalExample.Output field correctly so that tests
// work correctly under the interpreter. This requires that we
// do this step using ASTs, not *ssa.Functions---quite a
// redesign. See also the fake runExample in go/ssa/interp.
// Emit: array = new [n]testing.InternalTest
tArray := types.NewArray(tElem, int64(len(testfuncs)))
array := emitNew(fn, tArray, token.NoPos)
array.Comment = "test main"
for i, testfunc := range testfuncs {
// Emit: pitem = &array[i]
ia := &IndexAddr{X: array, Index: intConst(int64(i))}
ia.setType(tPtrElem)
pitem := fn.emit(ia)
// Emit: pname = &pitem.Name
fa := &FieldAddr{X: pitem, Field: 0} // .Name
fa.setType(tPtrString)
pname := fn.emit(fa)
// Emit: *pname = "testfunc"
emitStore(fn, pname, stringConst(testfunc.Name()), token.NoPos)
// Emit: pfunc = &pitem.F
fa = &FieldAddr{X: pitem, Field: 1} // .F
fa.setType(tPtrFunc)
pfunc := fn.emit(fa)
// Emit: *pfunc = testfunc
emitStore(fn, pfunc, testfunc, token.NoPos)
}
// Emit: slice array[:]
sl := &Slice{X: array}
sl.setType(slice)
return fn.emit(sl)
}
// Given the type of one of the three slice parameters of testing.Main,
// returns the function type.
func funcField(slice types.Type) *types.Signature {
return slice.(*types.Slice).Elem().Underlying().(*types.Struct).Field(1).Type().(*types.Signature)
}
// Plundered from $GOROOT/src/cmd/go/test.go
// isTest tells whether name looks like a test (or benchmark, according to prefix).
// It is a Test (say) if there is a character after Test that is not a lower-case letter.
// We don't want TesticularCancer.
func isTest(name, prefix string) bool {
if !strings.HasPrefix(name, prefix) {
return false
}
if len(name) == len(prefix) { // "Test" is ok
return true
}
return ast.IsExported(name[len(prefix):])
}