go-template: Only use cygpath on Git for Windows

As it turns out, regular MSYS2 and Cygwin do not work with with file
paths modified with `cygpath -m`. This change tries to ensure only Git
for Windows is affected by checking the `EXEPATH` variable.

Author: mbland

go-template

@@ -59,7 +59,7 @@ download_go_script_bash_tarball() {
   if [[ "$protocol" == "$url" ]]; then
     printf 'GO_SCRIPT_BASH_DOWNLOAD_URL has no protocol: %s\n' "$url" >&2
     return 1
-  elif command -v cygpath >/dev/null && [[ "$protocol" == 'file' ]]; then
+  elif [[ "$EXEPATH" =~ \\Git$ && "$protocol" == 'file' ]]; then
     url="file://$(cygpath -m "${url#file://}")"
   fi
 

tests/template.bats

@@ -42,8 +42,9 @@ CLONE_DIR=
 setup() {
   test_filter
   export GO_SCRIPT_BASH_{VERSION,REPO_URL,DOWNLOAD_URL}
-  NATIVE_LOCAL_URL="$(windows_native_path "$LOCAL_DOWNLOAD_URL")"
-  CLONE_DIR="$(windows_native_path "$TEST_GO_SCRIPTS_DIR")/go-script-bash"
+  NATIVE_LOCAL_URL="$(git_for_windows_native_path "$LOCAL_DOWNLOAD_URL")"
+  CLONE_DIR="$(git_for_windows_native_path "$TEST_GO_SCRIPTS_DIR")"
+  CLONE_DIR+='/go-script-bash'
   EXPECTED_URL="$FULL_DOWNLOAD_URL"
 
   if [[ -z "$TEST_USE_REAL_URL" ]]; then
@@ -73,22 +74,22 @@ assert_go_core_unpacked() {
   restore_bats_shell_options "$result"
 }
 
-# Converts a Unix path or 'file://' URL to a Windows native path.
+# Converts a Unix path or 'file://' URL to a Git for Windows native path.
 #
-# This is useful when passing file paths or URLs to native programs on MSYS2
-# or Cygwin, or validating the output of such programs, to ensure portability.
+# This is useful when passing file paths or URLs to native programs on Git for
+# Windows, or validating the output of such programs, to ensure portability.
 # The resulting path will contain forward slashes.
 #
 # Prints both converted and unconverted paths and URLs to standard output.
 #
 # Arguments:
 #   path:  Path or 'file://' URL to convert
-windows_native_path() {
+git_for_windows_native_path() {
   local path="$1"
   local protocol="${path%%://*}"
 
-  if ! command -v cygpath >/dev/null ||
-    [[ "$protocol" != "$path" && "$protocol" != 'file' ]]; then
+  if [[ ! "$EXEPATH" =~ \\Git$ && "$protocol" != "$path" &&
+    "$protocol" != 'file' ]]; then
     printf '%s' "$path"
   elif [[ "$protocol" == 'file' ]]; then
     printf 'file://'