Revert "testing: add TB.SetGOMAXPROCS function"

This reverts CL 519235.

Reason for revert: Proposal is still in incoming.

For #62020

Change-Id: Icccb930209f36097f5d930c01eda6b5042bdddc1
Reviewed-on: https://go-review.googlesource.com/c/go/+/573516
Reviewed-by: Than McIntosh <thanm@google.com>
Auto-Submit: Ian Lance Taylor <iant@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>

diff --git a/api/next/62020.txt b/api/next/62020.txt
deleted file mode 100644 (file)
index 3820d88..0000000
--- a/api/next/62020.txt
+++ /dev/null
@@ -1,4 +0,0 @@
-pkg testing, type TB interface, SetGOMAXPROCS(int) #62020
-pkg testing, method (*T) SetGOMAXPROCS(int) #62020
-pkg testing, method (*B) SetGOMAXPROCS(int) #62020
-pkg testing, method (*F) SetGOMAXPROCS(int) #62020

diff --git a/doc/next/6-stdlib/99-minor/testing/62020.md b/doc/next/6-stdlib/99-minor/testing/62020.md
deleted file mode 100644 (file)
index 3a73a1d..0000000
--- a/doc/next/6-stdlib/99-minor/testing/62020.md
+++ /dev/null
@@ -1 +0,0 @@
-The [`SetGOMAXPROCS`](/pkg/testing#T.SetGOMAXPROCS) method changes GOMAXPROCS for the duration of a single test.

diff --git a/src/testing/testing.go b/src/testing/testing.go
index a5441f24d5c23cd53f486dde1cbd159e7a7dffc7..5c06aea5f8fe6b8b0d18290a87a61da6d239bd9b 100644 (file)
--- a/src/testing/testing.go
+++ b/src/testing/testing.go
@@ -890,7 +890,6 @@ type TB interface {
        Logf(format string, args ...any)
        Name() string
        Setenv(key, value string)
-       SetGOMAXPROCS(n int)
        Skip(args ...any)
        SkipNow()
        Skipf(format string, args ...any)
@@ -917,9 +916,8 @@ var _ TB = (*B)(nil)
 // may be called simultaneously from multiple goroutines.
 type T struct {
        common
-       isEnvSet        bool
-       isGOMAXPROCSSet bool
-       context         *testContext // For running tests and subtests.
+       isEnvSet bool
+       context  *testContext // For running tests and subtests.
 }
 
 func (c *common) private() {}
@@ -1308,19 +1306,6 @@ func (c *common) Setenv(key, value string) {
        }
 }
 
-// SetGOMAXPROCS calls runtime.GOMAXPROCS(n) and uses Cleanup to
-// restore the value of GOMAXPROCS after the test.
-//
-// Because GOMAXPROCS affects the whole process, it cannot be used
-// in parallel tests or tests with parallel ancestors.
-func (c *common) SetGOMAXPROCS(n int) {
-       c.checkFuzzFn("SetGOMAXPROCS")
-       prev := runtime.GOMAXPROCS(n)
-       c.Cleanup(func() {
-               runtime.GOMAXPROCS(prev)
-       })
-}
-
 // panicHanding controls the panic handling used by runCleanup.
 type panicHandling int
 
@@ -1461,9 +1446,6 @@ func (t *T) Parallel() {
        if t.isEnvSet {
                panic("testing: t.Parallel called after t.Setenv; cannot set environment variables in parallel tests")
        }
-       if t.isGOMAXPROCSSet {
-               panic("testing: t.Parallel called after t.SetGOMAXPROCS; cannot set GOMAXPROCS in parallel tests")
-       }
        t.isParallel = true
        if t.parent.barrier == nil {
                // T.Parallel has no effect when fuzzing.
@@ -1545,33 +1527,6 @@ func (t *T) Setenv(key, value string) {
        t.common.Setenv(key, value)
 }
 
-// SetGOMAXPROCS calls runtime.GOMAXPROCS(n) and uses Cleanup to
-// restore the value of GOMAXPROCS after the test.
-//
-// Because GOMAXPROCS affects the whole process, it cannot be used
-// in parallel tests or tests with parallel ancestors.
-func (t *T) SetGOMAXPROCS(n int) {
-       // Non-parallel subtests that have parallel ancestors may still
-       // run in parallel with other tests: they are only non-parallel
-       // with respect to the other subtests of the same parent.
-       // Since SetGOMAXPROCS affects the whole process, we need to disallow it
-       // if the current test or any parent is parallel.
-       isParallel := false
-       for c := &t.common; c != nil; c = c.parent {
-               if c.isParallel {
-                       isParallel = true
-                       break
-               }
-       }
-       if isParallel {
-               panic("testing: t.SetGOMAXPROCS called after t.Parallel; cannot set GOMAXPROCS in parallel tests")
-       }
-
-       t.isGOMAXPROCSSet = true
-
-       t.common.SetGOMAXPROCS(n)
-}
-
 // InternalTest is an internal type but exported because it is cross-package;
 // it is part of the implementation of the "go test" command.
 type InternalTest struct {

diff --git a/src/testing/testing_test.go b/src/testing/testing_test.go
index 28b5809eea95c30920c7967e7179d5c9f505f671..d3822dfd578f803bf45cb196429f0ff997ce6016 100644 (file)
--- a/src/testing/testing_test.go
+++ b/src/testing/testing_test.go
@@ -13,7 +13,6 @@ import (
        "os/exec"
        "path/filepath"
        "regexp"
-       "runtime"
        "slices"
        "strings"
        "sync"
@@ -259,102 +258,6 @@ func TestSetenvWithParallelGrandParentBeforeSetenv(t *testing.T) {
        })
 }
 
-func TestSetGOMAXPROCS(t *testing.T) {
-       if runtime.GOARCH == "wasm" {
-               t.Skip("not supported on wasm yet")
-       }
-       tests := []struct {
-               name string
-               newP int
-       }{
-               {
-                       name: "overriding value",
-                       newP: 1,
-               },
-       }
-
-       for _, test := range tests {
-               p := runtime.GOMAXPROCS(0)
-               t.Run(test.name, func(t *testing.T) {
-                       t.SetGOMAXPROCS(test.newP + 1)
-                       if runtime.GOMAXPROCS(0) != test.newP+1 {
-                               t.Fatalf("unexpected value after t.SetGOMAXPROCS: got %d, want %d", runtime.GOMAXPROCS(0), test.newP+1)
-                       }
-               })
-               if runtime.GOMAXPROCS(0) != p {
-                       t.Fatalf("unexpected value after t.SetGOMAXPROCS cleanup: got %d, want %d", runtime.GOMAXPROCS(0), p)
-               }
-       }
-}
-
-func TestSetGOMAXPROCSWithParallelAfterSetGOMAXPROCS(t *testing.T) {
-       if runtime.GOARCH == "wasm" {
-               t.Skip("not supported on wasm yet")
-       }
-       defer func() {
-               want := "testing: t.Parallel called after t.SetGOMAXPROCS; cannot set GOMAXPROCS in parallel tests"
-               if got := recover(); got != want {
-                       t.Fatalf("expected panic; got %#v want %q", got, want)
-               }
-       }()
-       p := runtime.GOMAXPROCS(0)
-       t.SetGOMAXPROCS(p + 1)
-       t.Parallel()
-}
-
-func TestSetGOMAXPROCSWithParallelBeforeSetGOMAXPROCS(t *testing.T) {
-       if runtime.GOARCH == "wasm" {
-               t.Skip("not supported on wasm yet")
-       }
-       defer func() {
-               want := "testing: t.SetGOMAXPROCS called after t.Parallel; cannot set GOMAXPROCS in parallel tests"
-               if got := recover(); got != want {
-                       t.Fatalf("expected panic; got %#v want %q", got, want)
-               }
-       }()
-       t.Parallel()
-       p := runtime.GOMAXPROCS(0)
-       t.SetGOMAXPROCS(p + 1)
-}
-
-func TestSetGOMAXPROCSWithParallelParentBeforeSetGOMAXPROCS(t *testing.T) {
-       if runtime.GOARCH == "wasm" {
-               t.Skip("not supported on wasm yet")
-       }
-       t.Parallel()
-       t.Run("child", func(t *testing.T) {
-               defer func() {
-                       want := "testing: t.SetGOMAXPROCS called after t.Parallel; cannot set GOMAXPROCS in parallel tests"
-                       if got := recover(); got != want {
-                               t.Fatalf("expected panic; got %#v want %q", got, want)
-                       }
-               }()
-
-               p := runtime.GOMAXPROCS(0)
-               t.SetGOMAXPROCS(p + 1)
-       })
-}
-
-func TestSetGOMAXPROCSWithParallelGrandParentBeforeSetGOMAXPROCS(t *testing.T) {
-       if runtime.GOARCH == "wasm" {
-               t.Skip("not supported on wasm yet")
-       }
-       t.Parallel()
-       t.Run("child", func(t *testing.T) {
-               t.Run("grand-child", func(t *testing.T) {
-                       defer func() {
-                               want := "testing: t.SetGOMAXPROCS called after t.Parallel; cannot set GOMAXPROCS in parallel tests"
-                               if got := recover(); got != want {
-                                       t.Fatalf("expected panic; got %#v want %q", got, want)
-                               }
-                       }()
-
-                       p := runtime.GOMAXPROCS(0)
-                       t.SetGOMAXPROCS(p + 1)
-               })
-       })
-}
-
 // testingTrueInInit is part of TestTesting.
 var testingTrueInInit = false