AppVeyor: try to produce a better build version

I don't want to have to try and manually keep a version number in `appveyor.yml` up to date with any versioning for releases, etc.
This change tries to derive a reasonable version name from a Git tag, a pull request number, or a branch name (in that order).
I then append the AppVeyor build number to the end to try to ensure that we always have something unique (which is a requirement for AppVeyor).

1 files changed, 42 insertions, 9 deletions

diff --git a/appveyor.yml b/appveyor.yml
index abbcf100e..73f976d66 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -1,26 +1,59 @@
 
-# version format
-version: 0.0.{build}
+# Try to set AppVeyord build "version" to something reasonable,
+# based on what we are trying to build.
+init:
+  - ps: >-
+    if ($end:APPVEYOR_REPO_TAG -eq "true")
+    {
+        # If we are building from a tag in the repository,
+        # then use the tag name as the start of the build version
+        $versionName = "$($env:APPVEYOR_REPO_TAG_NAME.TrimStart("v"))"
+    }
+    else if($env:APPVEYOR_PULL_REQUEST_NUMBER)
+    {
+        # Otherwise, if we are building for a pull request,
+        # then use the pull request number to name our build version
+        $versionName = "pr$env:APPVEYOR_PULL_REQUEST_NUMBER"
+    }
+    else
+    {
+        # Otherwise, just set a build name based on the
+        # branch that we are building against
+        $versionName = "$env:APPVEYOR_REPO_BRANCH"
+    }
+    # Finally, we set the AppVeyor build version to use our version
+    # name with the build number appended.
+    #
+    # The string "appveyor" is being included before the build number
+    # in case we need to differentiate builds being made with different
+    # continuous integration providers.
+    Update-AppveyorBuild -Version "$versionName+appveyor.$env:APPVEYOR_BUILD_NUMBER"
 
-# build worker image
+# Our solution file is currently set up for VS2015
 image: Visual Studio 2015
 
-# script to run before build
+# The project uses a submodule for the "glslang" dependency,
+# so we need to make sure to pull that before building.
 install:
   - git submodule update --init --recursive
 
-# platforms to build
+# We want to build the full matrix of platforms and configurations
+# that we support on Windows.
 platform:
   - Win32
   - x64
-
-# configurations to build
 configuration:
   - Debug
   - Release
 
-# specify build settings
+# MSBUILD should ideally be able to find our solution file
+# automatically, but it seems to get confused, so we specify
+# the file name to use here.
 build:
   project: slang.sln
 
-# TODO: need to invoke test script here
+# TODO: need to invoke our test script as part of the build
+
+# TODO: need to figure out what we want to package for deployment
+
+# TODO: on a successful build of a tag, push to GitHub releases