anchor.diff:  :: --------------------
   :: Precedence is Git, VERSION_FILE, then DEFAULT_VERSION.
   :: Check if git is available by testing git describe.
  -CALL git describe>NUL 2>&1
  +CALL git describe --tags >NUL 2>&1
   IF NOT ERRORLEVEL 1 (
     SET fGIT_AVAILABLE=1
     :: Parse git version string
  
positive.code: 
  :: Builder checked out the parent of v1.0.0
  CALL git reset --hard v1.0.0~1 >NUL
  FOR /F "tokens=*" %%A IN ('"git describe HEAD"') DO SET tmp=%%A
  CALL :TEST_VERSION %tmp%
  
  :: Builder staged a file.
  CALL touch README >NUL
  CALL git add README
  FOR /F "tokens=*" %%A IN ('"git describe HEAD"') DO SET tmp=%%A
  CALL :TEST_VERSION %tmp%
  
  :: Builder checks out a tagged release and stages a file
  CALL git reset --hard v1.0.0 >NUL
  FOR /F "tokens=*" %%A IN ('"git describe HEAD"') DO SET tmp=%%A
  CALL touch README
  CALL git add README
  CALL :TEST_VERSION %tmp%
  
  :: Builder commits that file.
  CALL git commit -m "Modified Release" >NUL
  FOR /F "tokens=*" %%A IN ('"git describe HEAD"') DO SET tmp=%%A
  CALL :TEST_VERSION %tmp%
  
  :: Builder creates own tag
  CALL git tag v1.0.0-custom -m "Modified Release Tag"
  FOR /F "tokens=*" %%A IN ('"git describe HEAD"') DO SET tmp=%%A
  CALL :TEST_VERSION %tmp%
  
  :: Builder checked out a maint release and staged a file
  CALL git reset --hard v1.0.0.1 >NUL
  FOR /F "tokens=*" %%A IN ('"git describe HEAD"') DO SET tmp=%%A
  CALL touch README
  CALL git add README
  CALL :TEST_VERSION %tmp%
  
  :: Builder commits that file.
  CALL git commit -m "Modified Maint Release" >NUL
  FOR /F "tokens=*" %%A IN ('"git describe HEAD"') DO SET tmp=%%A
  CALL :TEST_VERSION %tmp%
  
  :: Builder creates own tag
  CALL git tag v1.0.0.1-custom -m "Modified Maint Release Tag"
  FOR /F "tokens=*" %%A IN ('"git describe HEAD"') DO SET tmp=%%A
  CALL :TEST_VERSION %tmp%
  
  ECHO.
  
negative.code: :: Full version releases have the Git patch count at the first '-' while
  :: pre-release versions have it at the second.
  IF [%USE_PRERELEASE_TAGS%] == [0] (
    FOR /F "tokens=2 delims=-" %%A IN ('"git describe --tags --match %tmp%"') DO (
      SET nbPATCHES_PART=%%A
    )
  ) ELSE (
    FOR /F "tokens=3 delims=-" %%A IN ('"git describe --tags --match %tmp%"') DO (
      SET nbPATCHES_PART=%%A
    )
  )
  