GTTF: Make it possible to pass sharding settings from command line.

This overrides any environment variables (a message is printed that
clearly says which settings are applied).

Main rationale is that runtest.py is well suited to pass command line
flags but not environment variables.

BUG=236893
R=sky@chromium.org

Review URL: https://codereview.chromium.org/58413003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@232869 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 44 insertions, 5 deletions

diff --git a/base/test/launcher/test_launcher.cc b/base/test/launcher/test_launcher.cc
index 0076634..1d0c8fe 100644
--- a/base/test/launcher/test_launcher.cc
+++ b/base/test/launcher/test_launcher.cc
@@ -552,14 +552,42 @@ bool TestLauncher::Init() {
     return false;
   }
 
-  if (!TakeInt32FromEnvironment(kTestTotalShards, &total_shards_))
-    return false;
-  if (!TakeInt32FromEnvironment(kTestShardIndex, &shard_index_))
-    return false;
+  // Initialize sharding. Command line takes precedence over legacy environment
+  // variables.
+  if (command_line->HasSwitch(switches::kTestLauncherTotalShards) &&
+      command_line->HasSwitch(switches::kTestLauncherShardIndex)) {
+    if (!StringToInt(
+            command_line->GetSwitchValueASCII(
+                switches::kTestLauncherTotalShards),
+            &total_shards_)) {
+      LOG(ERROR) << "Invalid value for " << switches::kTestLauncherTotalShards;
+      return false;
+    }
+    if (!StringToInt(
+            command_line->GetSwitchValueASCII(
+                switches::kTestLauncherShardIndex),
+            &shard_index_)) {
+      LOG(ERROR) << "Invalid value for " << switches::kTestLauncherShardIndex;
+      return false;
+    }
+    fprintf(stdout,
+            "Using sharding settings from command line. This is shard %d/%d\n",
+            shard_index_, total_shards_);
+    fflush(stdout);
+  } else {
+    if (!TakeInt32FromEnvironment(kTestTotalShards, &total_shards_))
+      return false;
+    if (!TakeInt32FromEnvironment(kTestShardIndex, &shard_index_))
+      return false;
+    fprintf(stdout,
+            "Using sharding settings from environment. This is shard %d/%d\n",
+            shard_index_, total_shards_);
+    fflush(stdout);
+  }
   if (shard_index_ < 0 ||
       total_shards_ < 0 ||
       shard_index_ >= total_shards_) {
-    LOG(ERROR) << "Invalid environment variables: we require 0 <= "
+    LOG(ERROR) << "Invalid sharding settings: we require 0 <= "
                << kTestShardIndex << " < " << kTestTotalShards
                << ", but you have " << kTestShardIndex << "=" << shard_index_
                << ", " << kTestTotalShards << "=" << total_shards_ << ".\n";
diff --git a/base/test/test_switches.cc b/base/test/test_switches.cc
index 18b4881..50b4513 100644
--- a/base/test/test_switches.cc
+++ b/base/test/test_switches.cc
@@ -26,6 +26,15 @@ const char switches::kTestLauncherSummaryOutput[] =
 const char switches::kTestLauncherPrintTestStdio[] =
     "test-launcher-print-test-stdio";
 
+// Index of the test shard to run, starting from 0 (first shard) to total shards
+// minus one (last shard).
+const char switches::kTestLauncherShardIndex[] =
+    "test-launcher-shard-index";
+
+// Total number of shards. Must be the same for all shards.
+const char switches::kTestLauncherTotalShards[] =
+    "test-launcher-total-shards";
+
 // Time (in milliseconds) that the tests should wait before timing out.
 const char switches::kTestLauncherTimeout[] = "test-launcher-timeout";
 // TODO(phajdan.jr): Clean up the switch names.
diff --git a/base/test/test_switches.h b/base/test/test_switches.h
index 330b925..a492058 100644
--- a/base/test/test_switches.h
+++ b/base/test/test_switches.h
@@ -15,6 +15,8 @@ extern const char kTestLauncherJobs[];
 extern const char kTestLauncherOutput[];
 extern const char kTestLauncherSummaryOutput[];
 extern const char kTestLauncherPrintTestStdio[];
+extern const char kTestLauncherShardIndex[];
+extern const char kTestLauncherTotalShards[];
 extern const char kTestLauncherTimeout[];
 extern const char kTestTinyTimeout[];
 extern const char kUiTestActionTimeout[];