Added assert_symlink_to

README.md

@@ -64,6 +64,24 @@ path : /path/to/existing-file
 --
 ```
 
+### `assert_symlink_to`
+
+Fail if the given file is not a symbolic to a defined target.
+
+```bash
+@test 'assert_symlink_to() {
+  assert_symlink_to /path/to/source-file /path/to/symlink
+}
+```
+
+On failure, the path is displayed.
+
+```
+-- symbolic link does not have the correct target --
+path : /path/to/symlink
+--
+```
+
 
 ## Working with temporary directories
 

src/file.bash

@@ -72,3 +72,36 @@ assert_file_not_exist() {
       | fail
   fi
 }
+
+# Fail and display path of the file (or directory) if it is not a symlink.
+#
+# Globals:
+#   BATSLIB_FILE_PATH_REM
+#   BATSLIB_FILE_PATH_ADD
+# Arguments:
+#   $1 - source
+#   $2 - destination
+# Returns:
+#   0 - link to correct target
+#   1 - otherwise
+# Outputs:
+#   STDERR - details, on failure
+assert_symlink_to() {
+  local -r sourcefile="$1"
+  local -r link="$2"
+  if [ ! -L $link   ]; then
+    local -r rem="$BATSLIB_FILE_PATH_REM"
+    local -r add="$BATSLIB_FILE_PATH_ADD"
+    batslib_print_kv_single 4 'path' "${link/$rem/$add}" \
+      | batslib_decorate 'file is not a symbolic link' \
+      | fail
+  fi
+  local -r realsource=$( readlink -f "$link" )
+  if [ ! "$realsource" = "$sourcefile"  ]; then
+    local -r rem="$BATSLIB_FILE_PATH_REM"
+    local -r add="$BATSLIB_FILE_PATH_ADD"
+    batslib_print_kv_single 4 'path' "${link/$rem/$add}" \
+      | batslib_decorate 'symbolic link does not have the correct target' \
+      | fail
+  fi
+}

test/50-assert-12-assert_symlink_to.bats

@@ -0,0 +1,25 @@
+#!/usr/bin/env bats
+
+load 'test_helper'
+fixtures 'symlink'
+
+# Correctness
+@test 'assert_symlink_to() <file> <link>: returns 0 if <link> exists and is a symbolic link to <file>' {
+  local -r file="${TEST_FIXTURE_ROOT}/file"
+  local -r link="${TEST_FIXTURE_ROOT}/link"
+  run assert_symlink_to $file $link
+  [ "$status" -eq 0 ]
+  [ "${#lines[@]}" -eq 0 ]
+}
+
+@test 'assert_symlink_to() <file> <link>: returns 1 and displays path if <link> is not a symbolic link to <file>' {
+  local -r file="${TEST_FIXTURE_ROOT}/dir/file.does_not_exist"
+  local -r link="${TEST_FIXTURE_ROOT}/link"
+  run assert_symlink_to $file $link
+  [ "$status" -eq 1 ]
+  [ "${#lines[@]}" -eq 3 ]
+  [ "${lines[0]}" == '-- symbolic link does not have the correct target --' ]
+  [ "${lines[1]}" == "path : $link" ]
+  [ "${lines[2]}" == '--' ]
+}
+

test/fixtures/symlink/symlink

@@ -0,0 +1 @@
+file