feat(files): add _randomLineFromFile_

.typos.toml

@@ -1,2 +1,9 @@
-[default.extend-words]
+[default]
+    default.locale = "en_us"
+
+    [default.extend-words]
+        curren = "curren" # Used in the context of '¤100'
         nd     = "nd"     # Used in the context of '2nd'
+
+[files]
+    extend-exclude = ["test/test_helper"]

README.md

@@ -236,6 +236,7 @@ Functions for working with files.
 -   **`_makeSymlink_`** Creates a symlink and backs up a file which may be overwritten by the new symlink. If the exact same symlink already exists, nothing is done.
 -   **`_parseYAML_`** Convert a YAML file into BASH variables for use in a shell script
 -   **`_printFileBetween_`** Prints block of text in a file between two regex patterns
+-   **`_randomLineFromFile_`** Prints a random line from a file
 -   **`_readFile_`** Prints each line of a file
 -   **`_sourceFile_`** Source a file into a script
 -   **`_createUniqueFilename_`** Ensure a file to be created has a unique filename to avoid overwriting other files

test/files.bats

@@ -301,6 +301,13 @@ _testParseYAML_() {
   assert_line --index 2 'line 3'
 }
 
+@test "_randomLineFromFile_" {
+  echo -e "line 1\nline 2\nline 3" > testfile.txt
+
+  run _randomLineFromFile_ "testfile.txt"
+  assert_output --regexp "^line [123]$"
+}
+
 @test "_sourceFile_ failure" {
   run _sourceFile_ "someNonExistentFile"
 

utilities/files.bash

@@ -749,6 +749,31 @@ _printFileBetween_() (
     fi
 )
 
+_randomLineFromFile_() {
+    # DESC:
+    #         Returns a random line from a file
+    # ARGS:
+    #         $1 (Required) - Input file
+    # OUTS:
+    #         Returns random line from file
+    # USAGE:
+    #         _randomLineFromFile_ "file.txt"
+
+    [[ $# == 0 ]] && fatal "Missing required argument to ${FUNCNAME[0]}"
+
+    local _fileToRead="$1"
+    local _rnd
+
+    [ ! -f "${_fileToRead}" ] \
+        && {
+            error "'${_fileToRead}' not found"
+            return 1
+        }
+
+    _rnd=$((1 + RANDOM % $(wc -l <"${_fileToRead}")))
+    sed -n "${_rnd}p" "${_fileToRead}"
+}
+
 _readFile_() {
     # DESC:
     #         Prints each line of a file