Merge pull request #129 from mbland/strings

Replace @go.remove_common_path_prefix with @go.common_parent_path

Author: mbland

lib/strings

@@ -21,6 +21,9 @@
 
 . "$_GO_USE_MODULES" 'validation'
 
+# DO NOT EDIT: Number of stack trace levels to skip when validation fails.
+export __GO_STRINGS_VALIDATION_SKIP_CALLERS=2
+
 # Splits fields from a delimited string into an array defined by the caller
 #
 # While `IFS= read -ra array_name <<<"$value"` is idiomatic, this function
@@ -72,7 +75,8 @@
 #   var_name:   Name of caller's variable to which to assign the common prefix
 #   ...:        Strings to examine to determine the common prefix
 @go.common_prefix() {
-  @go.validate_identifier_or_die 'Result variable name' "$1"
+  @go.validate_identifier_or_die 'Result variable name' "$1" \
+    "${__GO_STRINGS_VALIDATION_SKIP_CALLERS}"
   local _gcp_prefix="$2"
   local _gcp_prefix_len="${#_gcp_prefix}"
   local _gcp_item
@@ -93,24 +97,20 @@
   printf -v "$1" -- '%s' "$_gcp_prefix"
 }
 
-# Removes the common path prefix from a set of file paths
+# Determines the common parent directory path from a set of file paths
 #
 # Arguments:
-#   array_name:  Name of caller's array into which to store the updated paths
-#   ...:         File paths from which to remove the common path prefix
-@go.remove_common_path_prefix() {
-  @go.validate_identifier_or_die 'Result variable name' "$1"
-  local _grcpp_prefix
-  local _grcpp_paths=("${@:2}")
-
-  @go.common_prefix '_grcpp_prefix' "${_grcpp_paths[@]}"
+#   var_name:  Name of caller's variable to which to assign the parent path
+#   ...:       File paths to examine to determine the common parent directory
+@go.common_parent_path() {
+  ((++__GO_STRINGS_VALIDATION_SKIP_CALLERS))
+  @go.common_prefix "$1" "${@:2}"
+  ((--__GO_STRINGS_VALIDATION_SKIP_CALLERS))
 
-  if [[ "$_grcpp_prefix" =~ / ]]; then
-    _grcpp_prefix="${_grcpp_prefix%/*}/"
+  if [[ "${!1}" =~ / ]]; then
+    printf -v "$1" -- '%s' "${!1%/*}/"
   else
-    _grcpp_prefix=''
+    # Bash 3.2 won't perform the assignment if the format is the empty string.
+    printf -v "$1" '%s' ''
   fi
-
-  local IFS=$'\x1f'
-  read -ra "$1" <<<"${_grcpp_paths[*]#$_grcpp_prefix}"
 }

tests/strings/common-parent-path.bats

@@ -0,0 +1,56 @@
+#! /usr/bin/env bats
+
+load ../environment
+load helpers
+
+setup() {
+  test_filter
+  create_strings_test_script 'declare parent' \
+    '@go.common_parent_path "parent" "$@"' \
+    'printf -- "%s\n" "$parent"'
+}
+
+teardown() {
+  @go.remove_test_go_rootdir
+}
+
+@test "$SUITE: error if result variable name not a valid identifier" {
+  create_strings_test_script '@go.common_parent_path "invalid;" "$@"'
+  run "$TEST_GO_SCRIPT"
+
+  local err_msg='^Result variable name "invalid;" for @go.common_parent_path '
+  err_msg+='contains invalid identifier characters at:$'
+
+  assert_lines_match "$err_msg" \
+    "^  $TEST_GO_SCRIPT:[0-9] main$"
+}
+
+@test "$SUITE: empty argument list produces empty string" {
+  run "$TEST_GO_SCRIPT"
+  assert_success
+}
+
+@test "$SUITE: empty string produces empty string" {
+  run "$TEST_GO_SCRIPT" ''
+  assert_success
+}
+
+@test "$SUITE: single string returns empty string" {
+  run "$TEST_GO_SCRIPT" 'foo/bar/baz'
+  assert_success ''
+}
+
+@test "$SUITE: multiple paths with no common prefix returns empty string" {
+  run "$TEST_GO_SCRIPT" 'foobar/baz' 'foobaz/quux' 'fooquux/xyzzy'
+  assert_success ''
+}
+
+@test "$SUITE: multiple absolute paths with only root dir in common" {
+  run "$TEST_GO_SCRIPT" '/foobar/baz' '/foobaz/quux' '/fooquux/xyzzy'
+  assert_success '/'
+}
+
+@test "$SUITE: multiple paths with common parent path" {
+  run "$TEST_GO_SCRIPT" 'foo/bar/baz' 'foo/bar/quux/xyzzy' 'foo/baz/plugh'
+  assert_success 'foo/'
+}

tests/strings/common-prefix.bats

@@ -14,6 +14,17 @@ teardown() {
   @go.remove_test_go_rootdir
 }
 
+@test "$SUITE: error if result variable name not a valid identifier" {
+  create_strings_test_script '@go.common_prefix "invalid;" "$@"'
+  run "$TEST_GO_SCRIPT"
+
+  local err_msg='^Result variable name "invalid;" for @go.common_prefix '
+  err_msg+='contains invalid identifier characters at:$'
+
+  assert_lines_match "$err_msg" \
+    "^  $TEST_GO_SCRIPT:[0-9] main$"
+}
+
 @test "$SUITE: empty argument list produces empty string" {
   run "$TEST_GO_SCRIPT"
   assert_success