{all,clean,make,race,run}.bat: remove %GOBUILDEXIT% and %GOBUILDFAIL%

%GOBUILDEXIT% is used to avoid closing the terminal window when the
build or the tests fail on a dev machine. It is only set in CI to get
a non-zero exit code in case of failure.

%GOBUILDFAIL% is used to pass the exit code from a child batch file to
the parent batch file. It is set to 1 in the child batch file if the
build or the tests fail.

These two variables add complexity to the batch files and impose some
limitations on how they are implemented. For example, the child files
can't use setlocal, as it would make the parent file unable to read the
%GOBUILDFAIL% variable.

This CL removes these two variables and replaces them with unconditional
calls to "exit /b 1" in case of failure, which is more idiomatic and
composable. The trick is that the "/b" parameter makes the exit only
apply to the current batch file, not the entire shell session (unless
the bat file is the root, in which case the parameter is ignored), so
the parent batch file can continue executing, potentially checking the
errorlevel of the child batch file (which we always set to 1).

Change-Id: Ib053fb181ab14d58679551e03485700de77878d7
Reviewed-on: https://go-review.googlesource.com/c/go/+/647115
Auto-Submit: Damien Neil <dneil@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Damien Neil <dneil@google.com>

src/all.bat

@@ -8,15 +8,15 @@ setlocal
 
 if exist make.bat goto ok
 echo all.bat must be run from go\src
-:: cannot exit: would kill parent command interpreter
-goto end
+exit /b 1
 :ok
 
 call .\make.bat --no-banner --no-local
-if %GOBUILDFAIL%==1 goto end
+if errorlevel 1 goto fail
 call .\run.bat --no-rebuild --no-local
-if %GOBUILDFAIL%==1 goto end
+if errorlevel 1 goto fail
 "%GOTOOLDIR%/dist" banner
+goto :eof
 
-:end
-if x%GOBUILDEXIT%==x1 exit %GOBUILDFAIL%
+:fail
+exit /b 1

src/clean.bat

@@ -6,8 +6,6 @@
 
 setlocal
 
-set GOBUILDFAIL=0
-
 go tool dist env -w -p >env.bat
 if errorlevel 1 goto fail
 call .\env.bat
@@ -23,10 +21,7 @@ goto fail
 "%GOBIN%\go" tool dist clean
 "%GOBIN%\go" clean -i cmd
 
-goto end
+goto :eof
 
 :fail
-set GOBUILDFAIL=1
-
-:end
-if x%GOBUILDEXIT%==x1 exit %GOBUILDFAIL%
+exit /b 1

src/make.bat

@@ -47,8 +47,6 @@ if x%4==x--no-local goto nolocal
 setlocal
 :nolocal
 
-set GOBUILDFAIL=0
-
 if exist make.bat goto ok
 echo Must run make.bat from Go src directory.
 goto fail
@@ -180,5 +178,4 @@ echo ERROR: Cannot find %GOROOT_BOOTSTRAP%\bin\go.exe
 echo Set GOROOT_BOOTSTRAP to a working Go tree ^>= Go %bootgo%.
 
 :fail
-set GOBUILDFAIL=1
-if x%GOBUILDEXIT%==x1 exit %GOBUILDFAIL%
+exit /b 1

src/race.bat

@@ -11,8 +11,7 @@ setlocal
 
 if exist make.bat goto ok
 echo race.bat must be run from go\src
-:: cannot exit: would kill parent command interpreter
-goto end
+exit /b 1
 :ok
 
 set GOROOT=%CD%\..
@@ -29,7 +28,7 @@ goto fail
 
 :continue
 call .\make.bat --no-banner --no-local
-if %GOBUILDFAIL%==1 goto end
+if errorlevel 1 goto fail
 echo # go install -race std
 go install -race std
 if errorlevel 1 goto fail
@@ -37,15 +36,9 @@ if errorlevel 1 goto fail
 go tool dist test -race
 
 if errorlevel 1 goto fail
-goto succ
+echo All tests passed.
+goto :eof
 
 :fail
-set GOBUILDFAIL=1
 echo Fail.
-goto end
-
-:succ
-echo All tests passed.
-
-:end
-if x%GOBUILDEXIT%==x1 exit %GOBUILDFAIL%
+exit /b 1

src/run.bat

@@ -16,8 +16,6 @@ if x%2==x--no-local goto nolocal
 setlocal
 :nolocal
 
-set GOBUILDFAIL=0
-
 set GOENV=off
 ..\bin\go tool dist env > env.bat
 if errorlevel 1 goto fail
@@ -29,14 +27,12 @@ set GOPATH=c:\nonexist-gopath
 if x%1==x--no-rebuild goto norebuild
 ..\bin\go tool dist test --rebuild
 if errorlevel 1 goto fail
-goto end
+goto :eof
 
 :norebuild
 ..\bin\go tool dist test
 if errorlevel 1 goto fail
-goto end
+goto :eof
 
 :fail
-set GOBUILDFAIL=1
-
-:end
+exit /b 1