Fix compare_failures

+ and --force flag to always analysis past results (slower)

Change-Id: I9df760b61cfb71ecdf9a4b69d256895812f2eff1
Reviewed-on: https://dart-review.googlesource.com/50500
Commit-Queue: Johnni Winther <johnniwinther@google.com>
Reviewed-by: Alexander Thomas <athom@google.com>

Author: johnniwinther

tools/gardening/bin/compare_failures.dart

@@ -32,6 +32,8 @@ Future main(List<String> args) async {
   ArgParser argParser = createArgParser();
   argParser.addOption("run-count",
       defaultsTo: "10", help: "How many previous runs should be fetched");
+  argParser.addFlag("force",
+      abbr: "f", defaultsTo: false, help: "Force analysis of past results");
   argParser.addOption(Flags.commit,
       help: "Fetch result start from a given commit hash.");
   ArgResults argResults = argParser.parse(args);
@@ -50,6 +52,7 @@ Future main(List<String> args) async {
       runCount: runCount,
       commit: argResults[Flags.commit],
       verbose: argResults[Flags.verbose],
-      noCache: argResults[Flags.noCache]);
+      noCache: argResults[Flags.noCache],
+      forcePastResults: argResults["force"]);
   bot.close();
 }

tools/gardening/lib/src/compare_failures_impl.dart

@@ -21,13 +21,15 @@ Future mainInternal(Bot bot, List<String> args,
     {int runCount: 10,
     String commit,
     bool verbose: false,
-    bool noCache: false}) async {
+    bool noCache: false,
+    bool forcePastResults: false}) async {
   printBuildResultsSummary(
       await loadBuildResults(bot, args,
           runCount: runCount,
           commit: commit,
           verbose: verbose,
-          noCache: noCache),
+          noCache: noCache,
+          forcePastResults: forcePastResults),
       args);
 }
 
@@ -40,7 +42,8 @@ Future<Map<BuildUri, List<BuildResult>>> loadBuildResults(
     {int runCount: 10,
     String commit,
     bool verbose: false,
-    bool noCache: false}) async {
+    bool noCache: false,
+    bool forcePastResults: false}) async {
   List<BuildUri> buildUriList = <BuildUri>[];
   List<BuildDetail> buildDetails;
   if (commit != null) {
@@ -110,8 +113,9 @@ Future<Map<BuildUri, List<BuildResult>>> loadBuildResults(
   for (int index = 0; index < buildResults.length; index++) {
     BuildUri buildUri = buildUriList[index];
     BuildResult buildResult = buildResults[index];
-    List<BuildResult> results =
-        await readPastResults(bot, buildUri, buildResult, runCount);
+    List<BuildResult> results = await readPastResults(
+        bot, buildUri, buildResult, runCount,
+        forcePastResults: forcePastResults);
     pastResultsMap[buildUri] = results;
   }
   return pastResultsMap;
@@ -172,14 +176,15 @@ void printBuildResultsSummary(
 /// Creates a [BuildResult] for [buildUri] and, if it contains failures, the
 /// [BuildResult]s for the previous [runCount] builds.
 Future<List<BuildResult>> readPastResults(
-    Bot bot, BuildUri buildUri, BuildResult summary, int runCount) async {
+    Bot bot, BuildUri buildUri, BuildResult summary, int runCount,
+    {bool forcePastResults: false}) async {
   List<BuildResult> summaries = <BuildResult>[];
   if (summary == null) {
     print('No result found for $buildUri');
     return summaries;
   }
   summaries.add(summary);
-  if (summary.hasFailures) {
+  if (summary.hasFailures || forcePastResults) {
     summaries.addAll(await bot.readHistoricResults(summary.buildUri.prev(),
         previousCount: runCount - 1));
   }

tools/gardening/lib/src/logdog_rpc.dart

@@ -27,7 +27,7 @@ class LogdogRpc {
       StringBuffer buffer = new StringBuffer();
       json["logs"].forEach((log) {
         log["text"]["lines"].forEach((line) {
-          buffer.write(line["value"]);
+          buffer.writeln(line["value"]);
         });
       });
       return buffer.toString();