[dev.unified] all: merge master (85d87b9) into dev.unifieddev.unified

Merge List:

+ 2022-08-04 85d87b9c75 all: update vendored golang.org/x dependencies for Go 1.20 development
+ 2022-08-04 fb1bfd4d37 all: remove pre-Go 1.17 workarounds
+ 2022-08-04 44ff9bff0c runtime: clean up panic and deadlock lock ranks
+ 2022-08-04 f42dc0de74 runtime: make the lock rank DAG make more sense
+ 2022-08-04 d29a0282e9 runtime: add mayAcquire annotation for finlock
+ 2022-08-04 c5be4ed7df runtime: add missing trace lock edges
+ 2022-08-04 2b8a9a484f runtime: generate the lock ranking from a DAG description
+ 2022-08-04 ddfd639408 runtime: delete unused lock ranks
+ 2022-08-04 426ea5702b internal/dag: add a Graph type and make node order deterministic
+ 2022-08-04 d37cc9a8cd go/build, internal/dag: lift DAG parser into an internal package
+ 2022-08-04 ab0a94c6d3 cmd/dist: require Go 1.17 for building Go
+ 2022-08-04 1e3c19f3fe runtime: support riscv64 SV57 mode
+ 2022-08-03 f28fa952b5 make.bat, make.rc: show bootstrap toolchain version
+ 2022-08-03 87384801dc cmd/asm: update package doc to describe "-p" option
+ 2022-08-03 c6a2dada0d net: disable TestIPv6WriteMsgUDPAddrPortTargetAddrIPVersion [sic] on DragonflyBSD
+ 2022-08-02 29b9a328d2 runtime: trivial replacements of g in remaining files
+ 2022-08-02 c647264619 runtime: trivial replacements of g in signal_unix.go
+ 2022-08-02 399f50c9d7 runtime: tricky replacements of g in traceback.go
+ 2022-08-02 4509e951ec runtime: tricky replacements of g in proc.go
+ 2022-08-02 4400238ec8 runtime: trivial replacements of _g_ in remaining files
+ 2022-08-02 5999a28de8 runtime: trivial replacements of _g_ in os files
+ 2022-08-02 0e18cf6d09 runtime: trivial replacements of _g_ in GC files
+ 2022-08-02 4358a53a97 runtime: trivial replacements of _g_ in proc.go
+ 2022-08-02 b486518964 runtime: tricky replacements of _g_ in os3_solaris.go
+ 2022-08-02 54a0ab3f7b runtime: tricky replacements of _g_ in os3_plan9.go
+ 2022-08-02 4240ff764b runtime: tricky replacements of _g_ in signal_windows.go
+ 2022-08-02 8666d89ca8 runtime: tricky replacements of _g_ in signal_unix.go
+ 2022-08-02 74cee276fe runtime: tricky replacements of _g_ in trace.go
+ 2022-08-02 222799fde6 runtime: tricky replacements of _g_ in mgc.go
+ 2022-08-02 e9d7f54a1a runtime: tricky replacements of _g_ in proc.go
+ 2022-08-02 5e8d261918 runtime: rename _p_ to pp
+ 2022-08-02 0ad2ec6596 runtime: clean up dopanic_m
+ 2022-08-02 7e952962df runtime: clean up canpanic
+ 2022-08-02 9dbc0f3556 runtime: fix outdated g.m comment in traceback.go
+ 2022-08-02 d723df76da internal/goversion: update Version to 1.20
+ 2022-08-02 1b7e71e8ae all: disable tests that fail on Alpine
+ 2022-08-01 f2a9f3e2e0 test: improve generic type assertion test
+ 2022-08-01 27038b70f8 cmd/compile: fix wrong dict pass condition for type assertions
+ 2022-08-01 e99f53fed9 doc: move Go 1.19 release notes to x/website
+ 2022-08-01 8b13a073a1 doc: mention removal of cmd/compile's -importmap and -installsuffix flags
+ 2022-08-01 e95fd4c238 doc/go1.19: fix typo: EM_LONGARCH -> EM_LOONGARCH
+ 2022-08-01 dee3efd9f8 doc/go1.19: fix a few links that were missing trailing slashes
+ 2022-07-30 f32519e5fb runtime: fix typos
+ 2022-07-29 9a2001a8cc cmd/dist: always pass -short=true with -quick
+ 2022-07-28 5c8ec89cb5 doc/go1.19: minor adjustments and links
+ 2022-07-28 417be37048 doc/go1.19: improve the loong64 release notes
+ 2022-07-28 027855e8d8 os/exec: add GODEBUG setting to opt out of ErrDot changes

Change-Id: Idc0fbe93978c0dff7600b90a2c3ecc067fd9f5f2

1 files changed, 15 insertions, 218 deletions

diff --git a/src/go/build/deps_test.go b/src/go/build/deps_test.go
index 84cc9de8e7..e5f343a185 100644
--- a/src/go/build/deps_test.go
+++ b/src/go/build/deps_test.go
@@ -11,6 +11,7 @@ import (
 	"bytes"
 	"fmt"
 	"go/token"
+	"internal/dag"
 	"internal/testenv"
 	"io/fs"
 	"os"
@@ -29,40 +30,9 @@ import (
 // without prior discussion.
 // Negative assertions should almost never be removed.
 //
-// The general syntax of a rule is:
+// "a < b" means package b can import package a.
 //
-//	a, b < c, d;
-//
-// which means c and d come after a and b in the partial order
-// (that is, c and d can import a and b),
-// but doesn't provide a relative order between a vs b or c vs d.
-//
-// The rules can chain together, as in:
-//
-//	e < f, g < h;
-//
-// which is equivalent to
-//
-//	e < f, g;
-//	f, g < h;
-//
-// Except for the special bottom element "NONE", each name
-// must appear exactly once on the right-hand side of a rule.
-// That rule serves as the definition of the allowed dependencies
-// for that name. The definition must appear before any uses
-// of the name on the left-hand side of a rule. (That is, the
-// rules themselves must be ordered according to the partial
-// order, for easier reading by people.)
-//
-// Negative assertions double-check the partial order:
-//
-//	i !< j
-//
-// means that it must NOT be the case that i < j.
-// Negative assertions may appear anywhere in the rules,
-// even before i and j have been defined.
-//
-// Comments begin with #.
+// See `go doc internal/dag' for the full syntax.
 //
 // All-caps names are pseudo-names for specific points
 // in the dependency lattice.
@@ -177,7 +147,11 @@ var depsRules = `
 
 	os/signal, STR
 	< path/filepath
-	< io/ioutil, os/exec;
+	< io/ioutil;
+
+	os < internal/godebug;
+
+	path/filepath, internal/godebug < os/exec;
 
 	io/ioutil, os/exec, os/signal
 	< OS;
@@ -187,8 +161,6 @@ var depsRules = `
 	OS
 	< golang.org/x/sys/cpu;
 
-	os < internal/godebug;
-
 	# FMT is OS (which includes string routines) plus reflect and fmt.
 	# It does not include package log, which should be avoided in core packages.
 	strconv, unicode
@@ -206,6 +178,7 @@ var depsRules = `
 	# Misc packages needing only FMT.
 	FMT
 	< html,
+	  internal/dag,
 	  internal/goroot,
 	  mime/quotedprintable,
 	  net/internal/socktest,
@@ -624,11 +597,10 @@ func TestDependencies(t *testing.T) {
 		if sawImport[pkg] == nil {
 			sawImport[pkg] = map[string]bool{}
 		}
-		ok := policy[pkg]
 		var bad []string
 		for _, imp := range imports {
 			sawImport[pkg][imp] = true
-			if !ok[imp] {
+			if !policy.HasEdge(pkg, imp) {
 				bad = append(bad, imp)
 			}
 		}
@@ -697,187 +669,12 @@ func findImports(pkg string) ([]string, error) {
 }
 
 // depsPolicy returns a map m such that m[p][d] == true when p can import d.
-func depsPolicy(t *testing.T) map[string]map[string]bool {
-	allowed := map[string]map[string]bool{"NONE": {}}
-	disallowed := [][2][]string{}
-
-	parseDepsRules(t, func(deps []string, op string, users []string) {
-		if op == "!<" {
-			disallowed = append(disallowed, [2][]string{deps, users})
-			return
-		}
-		for _, u := range users {
-			if allowed[u] != nil {
-				t.Errorf("multiple deps lists for %s", u)
-			}
-			allowed[u] = make(map[string]bool)
-			for _, d := range deps {
-				if allowed[d] == nil {
-					t.Errorf("use of %s before its deps list", d)
-				}
-				allowed[u][d] = true
-			}
-		}
-	})
-
-	// Check for missing deps info.
-	for _, deps := range allowed {
-		for d := range deps {
-			if allowed[d] == nil {
-				t.Errorf("missing deps list for %s", d)
-			}
-		}
-	}
-
-	// Complete transitive allowed deps.
-	for k := range allowed {
-		for i := range allowed {
-			for j := range allowed {
-				if i != k && k != j && allowed[i][k] && allowed[k][j] {
-					if i == j {
-						// Can only happen along with a "use of X before deps" error above,
-						// but this error is more specific - it makes clear that reordering the
-						// rules will not be enough to fix the problem.
-						t.Errorf("deps policy cycle: %s < %s < %s", j, k, i)
-					}
-					allowed[i][j] = true
-				}
-			}
-		}
-	}
-
-	// Check negative assertions against completed allowed deps.
-	for _, bad := range disallowed {
-		deps, users := bad[0], bad[1]
-		for _, d := range deps {
-			for _, u := range users {
-				if allowed[u][d] {
-					t.Errorf("deps policy incorrect: assertion failed: %s !< %s", d, u)
-				}
-			}
-		}
-	}
-
-	if t.Failed() {
-		t.FailNow()
-	}
-
-	return allowed
-}
-
-// parseDepsRules parses depsRules, calling save(deps, op, users)
-// for each deps < users or deps !< users rule
-// (op is "<" or "!<").
-func parseDepsRules(t *testing.T, save func(deps []string, op string, users []string)) {
-	p := &depsParser{t: t, lineno: 1, text: depsRules}
-
-	var prev []string
-	var op string
-	for {
-		list, tok := p.nextList()
-		if tok == "" {
-			if prev == nil {
-				break
-			}
-			p.syntaxError("unexpected EOF")
-		}
-		if prev != nil {
-			save(prev, op, list)
-		}
-		prev = list
-		if tok == ";" {
-			prev = nil
-			op = ""
-			continue
-		}
-		if tok != "<" && tok != "!<" {
-			p.syntaxError("missing <")
-		}
-		op = tok
-	}
-}
-
-// A depsParser parses the depsRules syntax described above.
-type depsParser struct {
-	t        *testing.T
-	lineno   int
-	lastWord string
-	text     string
-}
-
-// syntaxError reports a parsing error.
-func (p *depsParser) syntaxError(msg string) {
-	p.t.Fatalf("deps:%d: syntax error: %s near %s", p.lineno, msg, p.lastWord)
-}
-
-// nextList parses and returns a comma-separated list of names.
-func (p *depsParser) nextList() (list []string, token string) {
-	for {
-		tok := p.nextToken()
-		switch tok {
-		case "":
-			if len(list) == 0 {
-				return nil, ""
-			}
-			fallthrough
-		case ",", "<", "!<", ";":
-			p.syntaxError("bad list syntax")
-		}
-		list = append(list, tok)
-
-		tok = p.nextToken()
-		if tok != "," {
-			return list, tok
-		}
-	}
-}
-
-// nextToken returns the next token in the deps rules,
-// one of ";" "," "<" "!<" or a name.
-func (p *depsParser) nextToken() string {
-	for {
-		if p.text == "" {
-			return ""
-		}
-		switch p.text[0] {
-		case ';', ',', '<':
-			t := p.text[:1]
-			p.text = p.text[1:]
-			return t
-
-		case '!':
-			if len(p.text) < 2 || p.text[1] != '<' {
-				p.syntaxError("unexpected token !")
-			}
-			p.text = p.text[2:]
-			return "!<"
-
-		case '#':
-			i := strings.Index(p.text, "\n")
-			if i < 0 {
-				i = len(p.text)
-			}
-			p.text = p.text[i:]
-			continue
-
-		case '\n':
-			p.lineno++
-			fallthrough
-		case ' ', '\t':
-			p.text = p.text[1:]
-			continue
-
-		default:
-			i := strings.IndexAny(p.text, "!;,<#\n \t")
-			if i < 0 {
-				i = len(p.text)
-			}
-			t := p.text[:i]
-			p.text = p.text[i:]
-			p.lastWord = t
-			return t
-		}
+func depsPolicy(t *testing.T) *dag.Graph {
+	g, err := dag.Parse(depsRules)
+	if err != nil {
+		t.Fatal(err)
 	}
+	return g
 }
 
 // TestStdlibLowercase tests that all standard library package names are