[build] Remove the last absolute paths from RBE builds.

Extend --check-clean (enabled on bots) to verify build commands don't include absolute paths.

The non-RBE GCC and MSVC builds still have absolute paths. GCC doesn't have -ffile-compilation-dir so it uses -fdebug-prefix-map, which is not fixable. The MSVC build has absolute path in the toolchain wrappers, which might be fixable.

TEST=ci
Change-Id: I3b984aaab7aefa7ff527f0a039ca42281224a09d
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/506505
Reviewed-by: Alexander Aprelev <aam@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>

build/rbe/rewrapper_dart.py

@@ -122,23 +122,6 @@ def find_inputs(uris, exec_root, package_config):
     return inputs
 
 
-# Rewrite absolute paths in an argument to be relative.
-def rewrite_absolute(arg, exec_root, working_directory):
-    # The file:// schema does not work with relative paths as they are parsed as
-    # the authority by the dart Uri class.
-    arg = arg.replace('file:///' + exec_root, '../../')
-    arg = arg.replace('file://' + exec_root, '../../')
-    # Replace the absolute exec root by a relative path to the exec root.
-    arg = arg.replace(exec_root, '../../')
-    # Simplify paths going to the exec root and back into the out directory.
-    # Carefully ensure the whole path isn't optimized away.
-    if arg.endswith(f'../../{working_directory}/'):
-        arg = arg.replace(f'../../{working_directory}/', '.')
-    else:
-        arg = arg.replace(f'../../{working_directory}/', '')
-    return arg
-
-
 # Parse the command line execution to recognize well known programs during the
 # Dart SDK build, so the inputs and output files can be determined, and the
 # command can be offloaded to RBE.
@@ -858,15 +841,7 @@ def main(argv):
     command.append('--labels=type=tool')
     command.append('--inputs=' + ','.join(paths))
     command.append('--output_files=' + ','.join(output_files))
-    # Absolute paths must not be used with RBE, but since the build currently
-    # heavily relies on them, work around this issue by rewriting the command
-    # to instead use relative paths. The Dart SDK build rules needs to be fixed
-    # rather than doing this, but this is an initial step towards that goal
-    # which will land in subsequent follow up changes.
-    command += argv[2:rewrapper_end] + [
-        rewrite_absolute(arg, rewrapper.exec_root, working_directory)
-        for arg in argv[rewrapper_end:]
-    ]
+    command += argv[2:]
 
     # Finally execute the command remotely.
     run_command(command, rewrapper.exec_strategy)

build/toolchain/mac/mac_toolchain.gni

@@ -171,7 +171,8 @@ template("mac_toolchain") {
         # to the link step. Which means we can't specify per target
         # entitlement files - and instead rely on dart_codesign.py script to
         # match binaries to their entitlement files by name.
-        signing_script = rebase_path("//runtime/tools/dart_codesign.py")
+        signing_script =
+            rebase_path("//runtime/tools/dart_codesign.py", root_build_dir)
         command += " && $signing_script --identity $codesigning_identity --binary $dylib"
       }
 
@@ -237,7 +238,8 @@ template("mac_toolchain") {
         # to the link step. Which means we can't specify per target
         # entitlement files - and instead rely on dart_codesign.py script to
         # match binaries to their entitlement files by name.
-        signing_script = rebase_path("//runtime/tools/dart_codesign.py")
+        signing_script =
+            rebase_path("//runtime/tools/dart_codesign.py", root_build_dir)
         binaries_to_sign = [
           "--binary",
           outfile,

runtime/vm/BUILD.gn

@@ -168,7 +168,7 @@ template("gen_vm_platform") {
           invoker.add_implicit_vm_platform_dependency
     }
     single_root_scheme = "org-dartlang-sdk"
-    single_root_base = rebase_path("../../")
+    single_root_base = rebase_path("../../", root_build_dir)
     libraries_specification_uri = "org-dartlang-sdk:///sdk/lib/libraries.json"
     outputs = [
       "$root_out_dir/vm_platform" + output_postfix + ".dill",

tools/build.py

@@ -198,10 +198,10 @@ def RunOneBuildCommand(build_config, args, env):
     return 0
 
 
-def CheckCleanBuild(build_config, args, env):
-    args = args + ['-n', '-d', 'explain']
-    print(' '.join(args))
-    process = subprocess.Popen(args,
+def CheckCleanBuild(build_config, args, rbe, env):
+    explain_args = args + ['-n', '-d', 'explain']
+    print(' '.join(explain_args))
+    process = subprocess.Popen(explain_args,
                                env=env,
                                stdout=subprocess.PIPE,
                                stderr=subprocess.PIPE,
@@ -209,10 +209,43 @@ def CheckCleanBuild(build_config, args, env):
     out, err = process.communicate()
     process.wait()
     if process.returncode != 0:
-        return 1
-    if 'ninja: no work to do' not in out.decode('utf-8'):
+        print(out.decode('utf-8'))
         print(err.decode('utf-8'))
         return 1
+    if 'ninja: no work to do' not in out.decode('utf-8'):
+        print(out.decode('utf-8'))
+        print(err.decode('utf-8'))
+        return 1
+
+    if rbe:
+        list_args = args + ['-t', 'commands']
+        print(' '.join(list_args))
+        process = subprocess.Popen(list_args,
+                                   env=env,
+                                   stdout=subprocess.PIPE,
+                                   stderr=subprocess.PIPE,
+                                   stdin=None)
+        out, err = process.communicate()
+        process.wait()
+        if process.returncode != 0:
+            print(out.decode('utf-8'))
+            print(err.decode('utf-8'))
+            return 1
+        bad_commands = []
+        working_dir = os.getcwd()
+        for command in out.decode('utf-8').splitlines():
+            if working_dir in command:
+                bad_commands.append(command)
+        if len(bad_commands) != 0:
+            print("""\
+
+error: Working directory found in build commands.
+Usually this means you forgot to use rebase_path(arg, root_build_dir) when passing arguments to a command.
+
+bad commands:""")
+            for command in bad_commands:
+                print(command)
+            return 1
 
     return 0
 
@@ -265,7 +298,7 @@ def Build(configs, env, options):
 
     if options.check_clean:
         for (build_config, args, rbe) in configs:
-            if CheckCleanBuild(build_config, args, env=env) != 0:
+            if CheckCleanBuild(build_config, args, rbe, env=env) != 0:
                 return 1
 
     return 0

utils/compiler/BUILD.gn

@@ -108,7 +108,7 @@ aot_snapshot("dart2js_sdk_aot_product") {
 
 compile_platform("compile_dart2js_platform") {
   single_root_scheme = "org-dartlang-sdk"
-  single_root_base = rebase_path("$sdk_root/")
+  single_root_base = rebase_path("$sdk_root/", root_build_dir)
   libraries_specification_uri = "org-dartlang-sdk:///lib/libraries.json"
 
   outputs = [
@@ -124,7 +124,7 @@ compile_platform("compile_dart2js_platform") {
 }
 compile_platform("compile_dart2js_server_platform") {
   single_root_scheme = "org-dartlang-sdk"
-  single_root_base = rebase_path("$sdk_root/")
+  single_root_base = rebase_path("$sdk_root/", root_build_dir)
   libraries_specification_uri = "org-dartlang-sdk:///lib/libraries.json"
 
   outputs = [

utils/dart2wasm/BUILD.gn

@@ -44,7 +44,7 @@ aot_snapshot("dart2wasm_product_snapshot") {
 
 compile_platform("compile_dart2wasm_platform") {
   single_root_scheme = "org-dartlang-sdk"
-  single_root_base = rebase_path("$sdk_root/")
+  single_root_base = rebase_path("$sdk_root/", root_build_dir)
   libraries_specification_uri = "org-dartlang-sdk:///lib/libraries.json"
 
   outputs = [
@@ -60,7 +60,7 @@ compile_platform("compile_dart2wasm_platform") {
 
 compile_platform("compile_dart2wasm_js_compatibility_platform") {
   single_root_scheme = "org-dartlang-sdk"
-  single_root_base = rebase_path("$sdk_root/")
+  single_root_base = rebase_path("$sdk_root/", root_build_dir)
   libraries_specification_uri = "org-dartlang-sdk:///lib/libraries.json"
 
   outputs = [
@@ -77,7 +77,7 @@ compile_platform("compile_dart2wasm_js_compatibility_platform") {
 
 compile_platform("compile_dart2wasm_standalone_platform") {
   single_root_scheme = "org-dartlang-sdk"
-  single_root_base = rebase_path("$sdk_root/")
+  single_root_base = rebase_path("$sdk_root/", root_build_dir)
   libraries_specification_uri = "org-dartlang-sdk:///lib/libraries.json"
 
   outputs = [

utils/ddc/BUILD.gn

@@ -409,7 +409,7 @@ ddc_compile("meta_canary_ddc_js") {
 
 compile_platform("ddc_platform") {
   single_root_scheme = "org-dartlang-sdk"
-  single_root_base = rebase_path("$sdk_root/")
+  single_root_base = rebase_path("$sdk_root/", root_build_dir)
   libraries_specification_uri = "org-dartlang-sdk:///lib/libraries.json"
 
   args = [