libgo: Merge from revision 18783:00cce3a34d7e of master library.

[official-gcc.git] / libgo / go / go / build / deps_test.go

// Copyright 2012 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.

// This file exercises the import parser but also checks that
// some low-level packages do not have new dependencies added.

package build

import (
        "sort"
        "testing"
)

// pkgDeps defines the expected dependencies between packages in
// the Go source tree.  It is a statement of policy.
// Changes should not be made to this map without prior discussion.
//
// The map contains two kinds of entries:
// 1) Lower-case keys are standard import paths and list the
// allowed imports in that package.
// 2) Upper-case keys define aliases for package sets, which can then
// be used as dependencies by other rules.
//
// DO NOT CHANGE THIS DATA TO FIX BUILDS.
//
var pkgDeps = map[string][]string{
        // L0 is the lowest level, core, nearly unavoidable packages.
        "errors":      {},
        "io":          {"errors", "sync"},
        "runtime":     {"unsafe"},
        "sync":        {"sync/atomic", "unsafe"},
        "sync/atomic": {"unsafe"},
        "unsafe":      {},

        "L0": {
                "errors",
                "io",
                "runtime",
                "sync",
                "sync/atomic",
                "unsafe",
        },

        // L1 adds simple functions and strings processing,
        // but not Unicode tables.
        "math":          {"unsafe"},
        "math/cmplx":    {"math"},
        "math/rand":     {"L0", "math"},
        "sort":          {},
        "strconv":       {"L0", "unicode/utf8", "math"},
        "unicode/utf16": {},
        "unicode/utf8":  {},

        "L1": {
                "L0",
                "math",
                "math/cmplx",
                "math/rand",
                "sort",
                "strconv",
                "unicode/utf16",
                "unicode/utf8",
        },

        // L2 adds Unicode and strings processing.
        "bufio":   {"L0", "unicode/utf8", "bytes"},
        "bytes":   {"L0", "unicode", "unicode/utf8"},
        "path":    {"L0", "unicode/utf8", "strings"},
        "strings": {"L0", "unicode", "unicode/utf8"},
        "unicode": {},

        "L2": {
                "L1",
                "bufio",
                "bytes",
                "path",
                "strings",
                "unicode",
        },

        // L3 adds reflection and some basic utility packages
        // and interface definitions, but nothing that makes
        // system calls.
        "crypto":              {"L2", "hash"},          // interfaces
        "crypto/cipher":       {"L2", "crypto/subtle"}, // interfaces
        "crypto/subtle":       {},
        "encoding/base32":     {"L2"},
        "encoding/base64":     {"L2"},
        "encoding/binary":     {"L2", "reflect"},
        "hash":                {"L2"}, // interfaces
        "hash/adler32":        {"L2", "hash"},
        "hash/crc32":          {"L2", "hash"},
        "hash/crc64":          {"L2", "hash"},
        "hash/fnv":            {"L2", "hash"},
        "image":               {"L2", "image/color"}, // interfaces
        "image/color":         {"L2"},                // interfaces
        "image/color/palette": {"L2", "image/color"},
        "reflect":             {"L2"},

        "L3": {
                "L2",
                "crypto",
                "crypto/cipher",
                "crypto/subtle",
                "encoding/base32",
                "encoding/base64",
                "encoding/binary",
                "hash",
                "hash/adler32",
                "hash/crc32",
                "hash/crc64",
                "hash/fnv",
                "image",
                "image/color",
                "image/color/palette",
                "reflect",
        },

        // End of linear dependency definitions.

        // Operating system access.
        "syscall":       {"L0", "unicode/utf16"},
        "time":          {"L0", "syscall"},
        "os":            {"L1", "os", "syscall", "time"},
        "path/filepath": {"L2", "os", "syscall"},
        "io/ioutil":     {"L2", "os", "path/filepath", "time"},
        "os/exec":       {"L2", "os", "syscall"},
        "os/signal":     {"L2", "os", "syscall"},

        // OS enables basic operating system functionality,
        // but not direct use of package syscall, nor os/signal.
        "OS": {
                "io/ioutil",
                "os",
                "os/exec",
                "path/filepath",
                "time",
        },

        // Formatted I/O: few dependencies (L1) but we must add reflect.
        "fmt": {"L1", "os", "reflect"},
        "log": {"L1", "os", "fmt", "time"},

        // Packages used by testing must be low-level (L2+fmt).
        "regexp":         {"L2", "regexp/syntax"},
        "regexp/syntax":  {"L2"},
        "runtime/debug":  {"L2", "fmt", "io/ioutil", "os", "time"},
        "runtime/pprof":  {"L2", "fmt", "text/tabwriter"},
        "text/tabwriter": {"L2"},

        "testing":        {"L2", "flag", "fmt", "os", "runtime/pprof", "time"},
        "testing/iotest": {"L2", "log"},
        "testing/quick":  {"L2", "flag", "fmt", "reflect"},

        // L4 is defined as L3+fmt+log+time, because in general once
        // you're using L3 packages, use of fmt, log, or time is not a big deal.
        "L4": {
                "L3",
                "fmt",
                "log",
                "time",
        },

        // Go parser.
        "go/ast":     {"L4", "OS", "go/scanner", "go/token"},
        "go/doc":     {"L4", "go/ast", "go/token", "regexp", "text/template"},
        "go/parser":  {"L4", "OS", "go/ast", "go/scanner", "go/token"},
        "go/printer": {"L4", "OS", "go/ast", "go/scanner", "go/token", "text/tabwriter"},
        "go/scanner": {"L4", "OS", "go/token"},
        "go/token":   {"L4"},

        "GOPARSER": {
                "go/ast",
                "go/doc",
                "go/parser",
                "go/printer",
                "go/scanner",
                "go/token",
        },

        // One of a kind.
        "archive/tar":         {"L4", "OS", "syscall"},
        "archive/zip":         {"L4", "OS", "compress/flate"},
        "compress/bzip2":      {"L4"},
        "compress/flate":      {"L4"},
        "compress/gzip":       {"L4", "compress/flate"},
        "compress/lzw":        {"L4"},
        "compress/zlib":       {"L4", "compress/flate"},
        "database/sql":        {"L4", "container/list", "database/sql/driver"},
        "database/sql/driver": {"L4", "time"},
        "debug/dwarf":         {"L4"},
        "debug/elf":           {"L4", "OS", "debug/dwarf"},
        "debug/gosym":         {"L4"},
        "debug/macho":         {"L4", "OS", "debug/dwarf"},
        "debug/pe":            {"L4", "OS", "debug/dwarf"},
        "encoding":            {"L4"},
        "encoding/ascii85":    {"L4"},
        "encoding/asn1":       {"L4", "math/big"},
        "encoding/csv":        {"L4"},
        "encoding/gob":        {"L4", "OS", "encoding"},
        "encoding/hex":        {"L4"},
        "encoding/json":       {"L4", "encoding"},
        "encoding/pem":        {"L4"},
        "encoding/xml":        {"L4", "encoding"},
        "flag":                {"L4", "OS"},
        "go/build":            {"L4", "OS", "GOPARSER"},
        "html":                {"L4"},
        "image/draw":          {"L4"},
        "image/gif":           {"L4", "compress/lzw", "image/color/palette", "image/draw"},
        "image/jpeg":          {"L4"},
        "image/png":           {"L4", "compress/zlib"},
        "index/suffixarray":   {"L4", "regexp"},
        "math/big":            {"L4"},
        "mime":                {"L4", "OS", "syscall"},
        "net/url":             {"L4"},
        "text/scanner":        {"L4", "OS"},
        "text/template/parse": {"L4"},

        "html/template": {
                "L4", "OS", "encoding/json", "html", "text/template",
                "text/template/parse",
        },
        "text/template": {
                "L4", "OS", "net/url", "text/template/parse",
        },

        // Cgo.
        "runtime/cgo": {"L0", "C"},
        "CGO":         {"C", "runtime/cgo"},

        // Fake entry to satisfy the pseudo-import "C"
        // that shows up in programs that use cgo.
        "C": {},

        // Plan 9 alone needs io/ioutil and os.
        "os/user": {"L4", "CGO", "io/ioutil", "os", "syscall"},

        // Basic networking.
        // Because net must be used by any package that wants to
        // do networking portably, it must have a small dependency set: just L1+basic os.
        "net": {"L1", "CGO", "os", "syscall", "time"},

        // NET enables use of basic network-related packages.
        "NET": {
                "net",
                "mime",
                "net/textproto",
                "net/url",
        },

        // Uses of networking.
        "log/syslog":    {"L4", "OS", "net"},
        "net/mail":      {"L4", "NET", "OS"},
        "net/textproto": {"L4", "OS", "net"},

        // Core crypto.
        "crypto/aes":    {"L3"},
        "crypto/des":    {"L3"},
        "crypto/hmac":   {"L3"},
        "crypto/md5":    {"L3"},
        "crypto/rc4":    {"L3"},
        "crypto/sha1":   {"L3"},
        "crypto/sha256": {"L3"},
        "crypto/sha512": {"L3"},

        "CRYPTO": {
                "crypto/aes",
                "crypto/des",
                "crypto/hmac",
                "crypto/md5",
                "crypto/rc4",
                "crypto/sha1",
                "crypto/sha256",
                "crypto/sha512",
        },

        // Random byte, number generation.
        // This would be part of core crypto except that it imports
        // math/big, which imports fmt.
        "crypto/rand": {"L4", "CRYPTO", "OS", "math/big", "syscall"},

        // Mathematical crypto: dependencies on fmt (L4) and math/big.
        // We could avoid some of the fmt, but math/big imports fmt anyway.
        "crypto/dsa":      {"L4", "CRYPTO", "math/big"},
        "crypto/ecdsa":    {"L4", "CRYPTO", "crypto/elliptic", "math/big"},
        "crypto/elliptic": {"L4", "CRYPTO", "math/big"},
        "crypto/rsa":      {"L4", "CRYPTO", "crypto/rand", "math/big"},

        "CRYPTO-MATH": {
                "CRYPTO",
                "crypto/dsa",
                "crypto/ecdsa",
                "crypto/elliptic",
                "crypto/rand",
                "crypto/rsa",
                "encoding/asn1",
                "math/big",
        },

        // SSL/TLS.
        "crypto/tls": {
                "L4", "CRYPTO-MATH", "CGO", "OS",
                "crypto/x509", "encoding/pem", "net", "syscall",
        },
        "crypto/x509": {
                "L4", "CRYPTO-MATH", "OS", "CGO",
                "crypto/x509/pkix", "encoding/pem", "encoding/hex", "net", "syscall",
        },
        "crypto/x509/pkix": {"L4", "CRYPTO-MATH"},

        // Simple net+crypto-aware packages.
        "mime/multipart": {"L4", "OS", "mime", "crypto/rand", "net/textproto"},
        "net/smtp":       {"L4", "CRYPTO", "NET", "crypto/tls"},

        // HTTP, kingpin of dependencies.
        "net/http": {
                "L4", "NET", "OS",
                "compress/gzip", "crypto/tls", "mime/multipart", "runtime/debug",
        },

        // HTTP-using packages.
        "expvar":            {"L4", "OS", "encoding/json", "net/http"},
        "net/http/cgi":      {"L4", "NET", "OS", "crypto/tls", "net/http", "regexp"},
        "net/http/fcgi":     {"L4", "NET", "OS", "net/http", "net/http/cgi"},
        "net/http/httptest": {"L4", "NET", "OS", "crypto/tls", "flag", "net/http"},
        "net/http/httputil": {"L4", "NET", "OS", "net/http"},
        "net/http/pprof":    {"L4", "OS", "html/template", "net/http", "runtime/pprof"},
        "net/rpc":           {"L4", "NET", "encoding/gob", "net/http", "text/template"},
        "net/rpc/jsonrpc":   {"L4", "NET", "encoding/json", "net/rpc"},
}

// isMacro reports whether p is a package dependency macro
// (uppercase name).
func isMacro(p string) bool {
        return 'A' <= p[0] && p[0] <= 'Z'
}

func allowed(pkg string) map[string]bool {
        m := map[string]bool{}
        var allow func(string)
        allow = func(p string) {
                if m[p] {
                        return
                }
                m[p] = true // set even for macros, to avoid loop on cycle

                // Upper-case names are macro-expanded.
                if isMacro(p) {
                        for _, pp := range pkgDeps[p] {
                                allow(pp)
                        }
                }
        }
        for _, pp := range pkgDeps[pkg] {
                allow(pp)
        }
        return m
}

var bools = []bool{false, true}
var geese = []string{"darwin", "dragonfly", "freebsd", "linux", "netbsd", "openbsd", "plan9", "solaris", "windows"}
var goarches = []string{"386", "amd64", "arm", "arm64"}

type osPkg struct {
        goos, pkg string
}

// allowedErrors are the operating systems and packages known to contain errors
// (currently just "no Go source files")
var allowedErrors = map[osPkg]bool{
        osPkg{"windows", "log/syslog"}: true,
        osPkg{"plan9", "log/syslog"}:   true,
}

func TestDependencies(t *testing.T) {
        var all []string

        for k := range pkgDeps {
                all = append(all, k)
        }
        sort.Strings(all)

        ctxt := Default
        test := func(mustImport bool) {
                for _, pkg := range all {
                        if isMacro(pkg) {
                                continue
                        }
                        p, err := ctxt.Import(pkg, "", 0)
                        if err != nil {
                                if allowedErrors[osPkg{ctxt.GOOS, pkg}] {
                                        continue
                                }
                                if !ctxt.CgoEnabled && pkg == "runtime/cgo" {
                                        continue
                                }
                                // Some of the combinations we try might not
                                // be reasonable (like arm,plan9,cgo), so ignore
                                // errors for the auto-generated combinations.
                                if !mustImport {
                                        continue
                                }
                                t.Errorf("%s/%s/cgo=%v %v", ctxt.GOOS, ctxt.GOARCH, ctxt.CgoEnabled, err)
                                continue
                        }
                        ok := allowed(pkg)
                        var bad []string
                        for _, imp := range p.Imports {
                                if !ok[imp] {
                                        bad = append(bad, imp)
                                }
                        }
                        if bad != nil {
                                t.Errorf("%s/%s/cgo=%v unexpected dependency: %s imports %v", ctxt.GOOS, ctxt.GOARCH, ctxt.CgoEnabled, pkg, bad)
                        }
                }
        }
        test(true)

        if testing.Short() {
                t.Logf("skipping other systems")
                return
        }

        for _, ctxt.GOOS = range geese {
                for _, ctxt.GOARCH = range goarches {
                        for _, ctxt.CgoEnabled = range bools {
                                test(false)
                        }
                }
        }
}