Establish more baseline tags.

So we can turn out a build string regardless of local conditions.

Author: paulp

tools/get-scala-revision

@@ -11,26 +11,31 @@
 [[ $# -eq 0 ]] || cd "$1"
 
 ensure_tag () {
-  # v2.10.0-M1
-  fallback=58cb15c40d
-  [[ -n $(git tag -l v2.10.0-M1) ]] || {
-    git tag -a -m "generated by get-scala-revision" v2.10.0-M1 $fallback
+  sha=$1
+  rev=$2
+  
+  [[ -n $(git tag -l $rev) ]] || {
+    git tag -a -m "generated by get-scala-revision" $rev $sha
   }
 }
-ensure_tag
+
+# Ensure some baseline tags are present so if this repository's
+# tags are screwed up or stale, we should still have a reference
+# point for a build string.
+ensure_tag 58cb15c40d v2.10.0-M1
+ensure_tag 29f3eace1e v2.9.1
+ensure_tag b0d78f6b9c v2.8.2
 
 # the closest tag, obtained separately because we have to
 # reconstruct the string around the padded distance.
-tag=$(git describe --match 'v2*' --abbrev=0)
+tag=$(git describe --tags --match 'v2*' --abbrev=0)
 
-# the full string - padding correctness depends on abbrev=10.
-described=$(git describe --match 'v2*' --abbrev=10)
+# printf %016s is not portable for 0-padding, has to be a digit.
+# so we're stuck disassembling it.
+described=$(git describe --tags --match 'v2*' --abbrev=10)
 suffix="${described##${tag}-}"
 counter=$(echo $suffix | cut -d - -f 1)
 hash=$(echo $suffix | cut -d - -f 2)
 
-# 016 is rocket-surgically-calibrated to pad the distance from the
-# tag to the current commit into a 4-digit number - since maven
-# will be treating this as a string, the ide depends on
-# 10 being greater than 9 (thus 0010 and 00009.)
-printf "%s-%04d-%10s-%s\n" "$tag" "$counter" "$hash" $(date "+%Y-%m-%d")
+# v2.10.0-M1-0098-g6f1c486d0b-2012-02-01
+printf "%s-%04d-%s-%s\n" "$tag" "$counter" "$hash" $(date "+%Y-%m-%d")