Parse the repo's version file when running from the repo.

sdk/lib/_internal/pub/lib/src/sdk.dart

Index: sdk/lib/_internal/pub/lib/src/sdk.dart
diff --git a/sdk/lib/_internal/pub/lib/src/sdk.dart b/sdk/lib/_internal/pub/lib/src/sdk.dart
index 2fe18588f599a85be0c06728b7af839b760f3293..d47cb52a7013929880183d59f1949ffe018ba49a 100644
--- a/sdk/lib/_internal/pub/lib/src/sdk.dart
+++ b/sdk/lib/_internal/pub/lib/src/sdk.dart
@@ -39,8 +39,36 @@ Version _getVersion() {
   var sdkVersion = Platform.environment["_PUB_TEST_SDK_VERSION"];
   if (sdkVersion != null) return new Version.parse(sdkVersion);
 
-  // Read the "version" file.
-  var revisionPath = path.join(_rootDirectory, "version");
-  var version = readTextFile(revisionPath).trim();
+  if (runningFromSdk) {

[nweiz, 2014/09/15 23:12:25]

Does this getter still return the right thing when running tests?

[Bob Nystrom, 2014/09/15 23:41:10]

The tests don't actually get this far. They set _PUB_TEST_SDK_VERSION. :)

+    // Read the "version" file.
+    var version = readTextFile(path.join(_rootDirectory, "version")).trim();
+    return new Version.parse(version);
+  }
+
+  // When running from the repo, read the canonical VERSION file in tools/.
+  // This makes it possible to run pub without having built the SDK first.

[nweiz, 2014/09/15 23:12:25]

Does this mean that our tests now depend on being run from a prebuilt SDK?

[Bob Nystrom, 2014/09/15 23:41:10]

Our tests would have previously required that if we weren't setting
_PUB_TEST_SDK_VERSION. This change means they no longer do.

+  var contents = readTextFile(path.join(repoRoot, "tools/VERSION"));
+
+  parseField(name) {
+    var pattern = new RegExp("^$name ([a-z0-9]+)", multiLine: true);
+    var match = pattern.firstMatch(contents);
+    return match[1];
+  }
+
+  var channel = parseField("CHANNEL");
+  var major = parseField("MAJOR");
+  var minor = parseField("MINOR");
+  var patch = parseField("PATCH");
+  var prerelease = parseField("PRERELEASE");
+  var prereleasePatch = parseField("PRERELEASE_PATCH");
+
+  var version = "$major.$minor.$patch";
+  if (channel == "be") {
+    // TODO(rnystrom): tools/utils.py includes the svn commit here. Should we?

[nweiz, 2014/09/15 23:12:26]

Probably? How painful is it to get?

[Bob Nystrom, 2014/09/15 23:41:10]

It's actually pretty hairy. 60 lines of Python that handles git, svn, git-svn,
and does a bunch of output parsing. I think we can get by with not having it. It
would only matter if there were version constraints that mentioned specific svn
commits, but we'd have much bigger problems if that was the case.

+    version += "-edge";
+  } else if (channel == "dev") {
+    version += "-dev.$prerelease.$prereleasePatch";
+  }
+
   return new Version.parse(version);
 }