From c62627cd037a85a5811695036528cd5ef4259aa2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jegors=20=C4=8Cemisovs?= <jegors_cemisovs@epam.com>
Date: Thu, 11 Apr 2024 17:08:24 +0300
Subject: [PATCH] Add "Bottle Song" exercise and test suite (#252)

* Add "Bottle Song" exercise and test suite

A new exercise called "Bottle Song" has been introduced. This includes corresponding test suite for the exercise. Modification was also made to update the average run time value in the config file. Overall, this commit provides a new practice exercise for users to solve.

* Update config file with reordering and run time adjustment

Repositioned the "Bottle Song" exercise in the configuration file for better flow. The average run time value for the test runner was also corrected from 2.0 to 2. These modifications should enhance the setup for users working through exercises.

* Add skip functionality to bottle-song tests

A condition to skip individual tests has been added to the test-bottle-song.bats file. This will allow us to selectively run or skip certain tests, providing a more flexible testing approach.
---
 config.json                                   |   8 +
 .../bottle-song/.docs/instructions.md         |  57 ++
 .../practice/bottle-song/.meta/config.json    |  19 +
 .../practice/bottle-song/.meta/example.awk    |  31 +
 .../practice/bottle-song/.meta/tests.toml     |  34 +
 .../practice/bottle-song/bats-extra.bash      | 637 ++++++++++++++++++
 .../practice/bottle-song/bottle-song.awk      |   8 +
 .../bottle-song/test-bottle-song.bats         | 153 +++++
 8 files changed, 947 insertions(+)
 create mode 100644 exercises/practice/bottle-song/.docs/instructions.md
 create mode 100644 exercises/practice/bottle-song/.meta/config.json
 create mode 100644 exercises/practice/bottle-song/.meta/example.awk
 create mode 100644 exercises/practice/bottle-song/.meta/tests.toml
 create mode 100644 exercises/practice/bottle-song/bats-extra.bash
 create mode 100644 exercises/practice/bottle-song/bottle-song.awk
 create mode 100644 exercises/practice/bottle-song/test-bottle-song.bats

diff --git a/config.json b/config.json
index b1d888c..fde1e14 100644
--- a/config.json
+++ b/config.json
@@ -314,6 +314,14 @@
         "prerequisites": [],
         "difficulty": 3
       },
+      {
+        "slug": "bottle-song",
+        "name": "Bottle Song",
+        "uuid": "bf5b0d3a-5a72-479c-94d6-da4f900e5a2c",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 3
+      },
       {
         "slug": "grade-school",
         "name": "Grade School",
diff --git a/exercises/practice/bottle-song/.docs/instructions.md b/exercises/practice/bottle-song/.docs/instructions.md
new file mode 100644
index 0000000..febdfc8
--- /dev/null
+++ b/exercises/practice/bottle-song/.docs/instructions.md
@@ -0,0 +1,57 @@
+# Instructions
+
+Recite the lyrics to that popular children's repetitive song: Ten Green Bottles.
+
+Note that not all verses are identical.
+
+```text
+Ten green bottles hanging on the wall,
+Ten green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be nine green bottles hanging on the wall.
+
+Nine green bottles hanging on the wall,
+Nine green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be eight green bottles hanging on the wall.
+
+Eight green bottles hanging on the wall,
+Eight green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be seven green bottles hanging on the wall.
+
+Seven green bottles hanging on the wall,
+Seven green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be six green bottles hanging on the wall.
+
+Six green bottles hanging on the wall,
+Six green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be five green bottles hanging on the wall.
+
+Five green bottles hanging on the wall,
+Five green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be four green bottles hanging on the wall.
+
+Four green bottles hanging on the wall,
+Four green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be three green bottles hanging on the wall.
+
+Three green bottles hanging on the wall,
+Three green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be two green bottles hanging on the wall.
+
+Two green bottles hanging on the wall,
+Two green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be one green bottle hanging on the wall.
+
+One green bottle hanging on the wall,
+One green bottle hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be no green bottles hanging on the wall.
+```
diff --git a/exercises/practice/bottle-song/.meta/config.json b/exercises/practice/bottle-song/.meta/config.json
new file mode 100644
index 0000000..acccd9d
--- /dev/null
+++ b/exercises/practice/bottle-song/.meta/config.json
@@ -0,0 +1,19 @@
+{
+  "authors": [
+    "rabestro"
+  ],
+  "files": {
+    "solution": [
+      "bottle-song.awk"
+    ],
+    "test": [
+      "test-bottle-song.bats"
+    ],
+    "example": [
+      ".meta/example.awk"
+    ]
+  },
+  "blurb": "Produce the lyrics to the popular children's repetitive song: Ten Green Bottles.",
+  "source": "Wikipedia",
+  "source_url": "https://en.wikipedia.org/wiki/Ten_Green_Bottles"
+}
diff --git a/exercises/practice/bottle-song/.meta/example.awk b/exercises/practice/bottle-song/.meta/example.awk
new file mode 100644
index 0000000..daccbc9
--- /dev/null
+++ b/exercises/practice/bottle-song/.meta/example.awk
@@ -0,0 +1,31 @@
+# These variables are initialized on the command line (using '-v'):
+# - startBottles
+# - takeDown
+
+BEGIN {
+    split("One Two Three Four Five Six Seven Eight Nine Ten", Numbers)
+
+    while (takeDown--) {
+        print_verse(startBottles--)
+        if (takeDown) print ""
+    }
+}
+
+function print_verse(bottles) {
+    print first_line(bottles)
+    print first_line(bottles)
+    print "And if one green bottle should accidentally fall,"
+    print last_line(bottles - 1)
+}
+
+function first_line(bottles) {
+    return Numbers[bottles] hanging(bottles) ","
+}
+
+function last_line(bottles) {
+    return "There'll be " tolower(bottles == 0 ? "no" : Numbers[bottles]) hanging(bottles) "."
+}
+
+function hanging(bottles) {
+    return " green bottle" (bottles == 1 ? "" : "s") " hanging on the wall"
+}
diff --git a/exercises/practice/bottle-song/.meta/tests.toml b/exercises/practice/bottle-song/.meta/tests.toml
new file mode 100644
index 0000000..306cf88
--- /dev/null
+++ b/exercises/practice/bottle-song/.meta/tests.toml
@@ -0,0 +1,34 @@
+# This is an auto-generated file.
+#
+# Regenerating this file via `configlet sync` will:
+# - Recreate every `description` key/value pair
+# - Recreate every `reimplements` key/value pair, where they exist in problem-specifications
+# - Remove any `include = true` key/value pair (an omitted `include` key implies inclusion)
+# - Preserve any other key/value pair
+#
+# As user-added comments (using the # character) will be removed when this file
+# is regenerated, comments can be added via a `comment` key.
+
+[5a02fd08-d336-4607-8006-246fe6fa9fb0]
+description = "verse -> single verse -> first generic verse"
+
+[77299ca6-545e-4217-a9cc-606b342e0187]
+description = "verse -> single verse -> last generic verse"
+
+[102cbca0-b197-40fd-b548-e99609b06428]
+description = "verse -> single verse -> verse with 2 bottles"
+
+[b8ef9fce-960e-4d85-a0c9-980a04ec1972]
+description = "verse -> single verse -> verse with 1 bottle"
+
+[c59d4076-f671-4ee3-baaa-d4966801f90d]
+description = "verse -> single verse -> verse with 0 bottles"
+
+[7e17c794-402d-4ca6-8f96-4d8f6ee1ec7e]
+description = "lyrics -> multiple verses -> first two verses"
+
+[949868e7-67e8-43d3-9bb4-69277fe020fb]
+description = "lyrics -> multiple verses -> last three verses"
+
+[bc220626-126c-4e72-8df4-fddfc0c3e458]
+description = "lyrics -> multiple verses -> all verses"
diff --git a/exercises/practice/bottle-song/bats-extra.bash b/exercises/practice/bottle-song/bats-extra.bash
new file mode 100644
index 0000000..54d4807
--- /dev/null
+++ b/exercises/practice/bottle-song/bats-extra.bash
@@ -0,0 +1,637 @@
+# This is the source code for bats-support and bats-assert, concatenated
+# * https://github.com/bats-core/bats-support
+# * https://github.com/bats-core/bats-assert
+#
+# Comments have been removed to save space. See the git repos for full source code.
+
+############################################################
+#
+# bats-support - Supporting library for Bats test helpers
+#
+# Written in 2016 by Zoltan Tombol <zoltan dot tombol at gmail dot com>
+#
+# To the extent possible under law, the author(s) have dedicated all
+# copyright and related and neighboring rights to this software to the
+# public domain worldwide. This software is distributed without any
+# warranty.
+#
+# You should have received a copy of the CC0 Public Domain Dedication
+# along with this software. If not, see
+# <http://creativecommons.org/publicdomain/zero/1.0/>.
+#
+
+fail() {
+  (( $# == 0 )) && batslib_err || batslib_err "$@"
+  return 1
+}
+
+batslib_is_caller() {
+  local -i is_mode_direct=1
+
+  # Handle options.
+  while (( $# > 0 )); do
+    case "$1" in
+      -i|--indirect) is_mode_direct=0; shift ;;
+      --) shift; break ;;
+      *) break ;;
+    esac
+  done
+
+  # Arguments.
+  local -r func="$1"
+
+  # Check call stack.
+  if (( is_mode_direct )); then
+    [[ $func == "${FUNCNAME[2]}" ]] && return 0
+  else
+    local -i depth
+    for (( depth=2; depth<${#FUNCNAME[@]}; ++depth )); do
+      [[ $func == "${FUNCNAME[$depth]}" ]] && return 0
+    done
+  fi
+
+  return 1
+}
+
+batslib_err() {
+  { if (( $# > 0 )); then
+      echo "$@"
+    else
+      cat -
+    fi
+  } >&2
+}
+
+batslib_count_lines() {
+  local -i n_lines=0
+  local line
+  while IFS='' read -r line || [[ -n $line ]]; do
+    (( ++n_lines ))
+  done < <(printf '%s' "$1")
+  echo "$n_lines"
+}
+
+batslib_is_single_line() {
+  for string in "$@"; do
+    (( $(batslib_count_lines "$string") > 1 )) && return 1
+  done
+  return 0
+}
+
+batslib_get_max_single_line_key_width() {
+  local -i max_len=-1
+  while (( $# != 0 )); do
+    local -i key_len="${#1}"
+    batslib_is_single_line "$2" && (( key_len > max_len )) && max_len="$key_len"
+    shift 2
+  done
+  echo "$max_len"
+}
+
+batslib_print_kv_single() {
+  local -ir col_width="$1"; shift
+  while (( $# != 0 )); do
+    printf '%-*s : %s\n' "$col_width" "$1" "$2"
+    shift 2
+  done
+}
+
+batslib_print_kv_multi() {
+  while (( $# != 0 )); do
+    printf '%s (%d lines):\n' "$1" "$( batslib_count_lines "$2" )"
+    printf '%s\n' "$2"
+    shift 2
+  done
+}
+
+batslib_print_kv_single_or_multi() {
+  local -ir width="$1"; shift
+  local -a pairs=( "$@" )
+
+  local -a values=()
+  local -i i
+  for (( i=1; i < ${#pairs[@]}; i+=2 )); do
+    values+=( "${pairs[$i]}" )
+  done
+
+  if batslib_is_single_line "${values[@]}"; then
+    batslib_print_kv_single "$width" "${pairs[@]}"
+  else
+    local -i i
+    for (( i=1; i < ${#pairs[@]}; i+=2 )); do
+      pairs[$i]="$( batslib_prefix < <(printf '%s' "${pairs[$i]}") )"
+    done
+    batslib_print_kv_multi "${pairs[@]}"
+  fi
+}
+
+batslib_prefix() {
+  local -r prefix="${1:-  }"
+  local line
+  while IFS='' read -r line || [[ -n $line ]]; do
+    printf '%s%s\n' "$prefix" "$line"
+  done
+}
+
+batslib_mark() {
+  local -r symbol="$1"; shift
+  # Sort line numbers.
+  set -- $( sort -nu <<< "$( printf '%d\n' "$@" )" )
+
+  local line
+  local -i idx=0
+  while IFS='' read -r line || [[ -n $line ]]; do
+    if (( ${1:--1} == idx )); then
+      printf '%s\n' "${symbol}${line:${#symbol}}"
+      shift
+    else
+      printf '%s\n' "$line"
+    fi
+    (( ++idx ))
+  done
+}
+
+batslib_decorate() {
+  echo
+  echo "-- $1 --"
+  cat -
+  echo '--'
+  echo
+}
+
+############################################################
+
+assert() {
+  if ! "$@"; then
+    batslib_print_kv_single 10 'expression' "$*" \
+    | batslib_decorate 'assertion failed' \
+    | fail
+  fi
+}
+
+assert_equal() {
+  if [[ $1 != "$2" ]]; then
+    batslib_print_kv_single_or_multi 8 \
+    'expected' "$2" \
+    'actual'   "$1" \
+    | batslib_decorate 'values do not equal' \
+    | fail
+  fi
+}
+
+assert_failure() {
+  : "${output?}"
+  : "${status?}"
+
+  (( $# > 0 )) && local -r expected="$1"
+  if (( status == 0 )); then
+    batslib_print_kv_single_or_multi 6 'output' "$output" \
+    | batslib_decorate 'command succeeded, but it was expected to fail' \
+    | fail
+  elif (( $# > 0 )) && (( status != expected )); then
+    { local -ir width=8
+      batslib_print_kv_single "$width" \
+      'expected' "$expected" \
+      'actual'   "$status"
+      batslib_print_kv_single_or_multi "$width" \
+      'output' "$output"
+    } \
+    | batslib_decorate 'command failed as expected, but status differs' \
+    | fail
+  fi
+}
+
+assert_line() {
+  local -i is_match_line=0
+  local -i is_mode_partial=0
+  local -i is_mode_regexp=0
+  : "${lines?}"
+
+  # Handle options.
+  while (( $# > 0 )); do
+    case "$1" in
+    -n|--index)
+      if (( $# < 2 )) || ! [[ $2 =~ ^([0-9]|[1-9][0-9]+)$ ]]; then
+        echo "\`--index' requires an integer argument: \`$2'" \
+        | batslib_decorate 'ERROR: assert_line' \
+        | fail
+        return $?
+      fi
+      is_match_line=1
+      local -ri idx="$2"
+      shift 2
+      ;;
+    -p|--partial) is_mode_partial=1; shift ;;
+    -e|--regexp) is_mode_regexp=1; shift ;;
+    --) shift; break ;;
+    *) break ;;
+    esac
+  done
+
+  if (( is_mode_partial )) && (( is_mode_regexp )); then
+    echo "\`--partial' and \`--regexp' are mutually exclusive" \
+    | batslib_decorate 'ERROR: assert_line' \
+    | fail
+    return $?
+  fi
+
+  # Arguments.
+  local -r expected="$1"
+
+  if (( is_mode_regexp == 1 )) && [[ '' =~ $expected ]] || (( $? == 2 )); then
+    echo "Invalid extended regular expression: \`$expected'" \
+    | batslib_decorate 'ERROR: assert_line' \
+    | fail
+    return $?
+  fi
+
+  # Matching.
+  if (( is_match_line )); then
+    # Specific line.
+    if (( is_mode_regexp )); then
+      if ! [[ ${lines[$idx]} =~ $expected ]]; then
+        batslib_print_kv_single 6 \
+        'index' "$idx" \
+        'regexp' "$expected" \
+        'line'  "${lines[$idx]}" \
+        | batslib_decorate 'regular expression does not match line' \
+        | fail
+      fi
+    elif (( is_mode_partial )); then
+      if [[ ${lines[$idx]} != *"$expected"* ]]; then
+        batslib_print_kv_single 9 \
+        'index'     "$idx" \
+        'substring' "$expected" \
+        'line'      "${lines[$idx]}" \
+        | batslib_decorate 'line does not contain substring' \
+        | fail
+      fi
+    else
+      if [[ ${lines[$idx]} != "$expected" ]]; then
+        batslib_print_kv_single 8 \
+        'index'    "$idx" \
+        'expected' "$expected" \
+        'actual'   "${lines[$idx]}" \
+        | batslib_decorate 'line differs' \
+        | fail
+      fi
+    fi
+  else
+    # Contained in output.
+    if (( is_mode_regexp )); then
+      local -i idx
+      for (( idx = 0; idx < ${#lines[@]}; ++idx )); do
+        [[ ${lines[$idx]} =~ $expected ]] && return 0
+      done
+      { local -ar single=( 'regexp' "$expected" )
+        local -ar may_be_multi=( 'output' "$output" )
+        local -ir width="$( batslib_get_max_single_line_key_width "${single[@]}" "${may_be_multi[@]}" )"
+        batslib_print_kv_single "$width" "${single[@]}"
+        batslib_print_kv_single_or_multi "$width" "${may_be_multi[@]}"
+      } \
+      | batslib_decorate 'no output line matches regular expression' \
+      | fail
+    elif (( is_mode_partial )); then
+      local -i idx
+      for (( idx = 0; idx < ${#lines[@]}; ++idx )); do
+        [[ ${lines[$idx]} == *"$expected"* ]] && return 0
+      done
+      { local -ar single=( 'substring' "$expected" )
+        local -ar may_be_multi=( 'output' "$output" )
+        local -ir width="$( batslib_get_max_single_line_key_width "${single[@]}" "${may_be_multi[@]}" )"
+        batslib_print_kv_single "$width" "${single[@]}"
+        batslib_print_kv_single_or_multi "$width" "${may_be_multi[@]}"
+      } \
+      | batslib_decorate 'no output line contains substring' \
+      | fail
+    else
+      local -i idx
+      for (( idx = 0; idx < ${#lines[@]}; ++idx )); do
+        [[ ${lines[$idx]} == "$expected" ]] && return 0
+      done
+      { local -ar single=( 'line' "$expected" )
+        local -ar may_be_multi=( 'output' "$output" )
+        local -ir width="$( batslib_get_max_single_line_key_width "${single[@]}" "${may_be_multi[@]}" )"
+        batslib_print_kv_single "$width" "${single[@]}"
+        batslib_print_kv_single_or_multi "$width" "${may_be_multi[@]}"
+      } \
+      | batslib_decorate 'output does not contain line' \
+      | fail
+    fi
+  fi
+}
+
+assert_output() {
+  local -i is_mode_partial=0
+  local -i is_mode_regexp=0
+  local -i is_mode_nonempty=0
+  local -i use_stdin=0
+  : "${output?}"
+
+  # Handle options.
+  if (( $# == 0 )); then
+    is_mode_nonempty=1
+  fi
+
+  while (( $# > 0 )); do
+    case "$1" in
+    -p|--partial) is_mode_partial=1; shift ;;
+    -e|--regexp) is_mode_regexp=1; shift ;;
+    -|--stdin) use_stdin=1; shift ;;
+    --) shift; break ;;
+    *) break ;;
+    esac
+  done
+
+  if (( is_mode_partial )) && (( is_mode_regexp )); then
+    echo "\`--partial' and \`--regexp' are mutually exclusive" \
+    | batslib_decorate 'ERROR: assert_output' \
+    | fail
+    return $?
+  fi
+
+  # Arguments.
+  local expected
+  if (( use_stdin )); then
+    expected="$(cat -)"
+  else
+    expected="${1-}"
+  fi
+
+  # Matching.
+  if (( is_mode_nonempty )); then
+    if [ -z "$output" ]; then
+      echo 'expected non-empty output, but output was empty' \
+      | batslib_decorate 'no output' \
+      | fail
+    fi
+  elif (( is_mode_regexp )); then
+    if [[ '' =~ $expected ]] || (( $? == 2 )); then
+      echo "Invalid extended regular expression: \`$expected'" \
+      | batslib_decorate 'ERROR: assert_output' \
+      | fail
+    elif ! [[ $output =~ $expected ]]; then
+      batslib_print_kv_single_or_multi 6 \
+      'regexp'  "$expected" \
+      'output' "$output" \
+      | batslib_decorate 'regular expression does not match output' \
+      | fail
+    fi
+  elif (( is_mode_partial )); then
+    if [[ $output != *"$expected"* ]]; then
+      batslib_print_kv_single_or_multi 9 \
+      'substring' "$expected" \
+      'output'    "$output" \
+      | batslib_decorate 'output does not contain substring' \
+      | fail
+    fi
+  else
+    if [[ $output != "$expected" ]]; then
+      batslib_print_kv_single_or_multi 8 \
+      'expected' "$expected" \
+      'actual'   "$output" \
+      | batslib_decorate 'output differs' \
+      | fail
+    fi
+  fi
+}
+
+assert_success() {
+  : "${output?}"
+  : "${status?}"
+
+  if (( status != 0 )); then
+    { local -ir width=6
+      batslib_print_kv_single "$width" 'status' "$status"
+      batslib_print_kv_single_or_multi "$width" 'output' "$output"
+    } \
+    | batslib_decorate 'command failed' \
+    | fail
+  fi
+}
+
+refute() {
+  if "$@"; then
+    batslib_print_kv_single 10 'expression' "$*" \
+    | batslib_decorate 'assertion succeeded, but it was expected to fail' \
+    | fail
+  fi
+}
+
+refute_line() {
+  local -i is_match_line=0
+  local -i is_mode_partial=0
+  local -i is_mode_regexp=0
+  : "${lines?}"
+
+  # Handle options.
+  while (( $# > 0 )); do
+    case "$1" in
+    -n|--index)
+      if (( $# < 2 )) || ! [[ $2 =~ ^([0-9]|[1-9][0-9]+)$ ]]; then
+        echo "\`--index' requires an integer argument: \`$2'" \
+        | batslib_decorate 'ERROR: refute_line' \
+        | fail
+        return $?
+      fi
+      is_match_line=1
+      local -ri idx="$2"
+      shift 2
+      ;;
+    -p|--partial) is_mode_partial=1; shift ;;
+    -e|--regexp) is_mode_regexp=1; shift ;;
+    --) shift; break ;;
+    *) break ;;
+    esac
+  done
+
+  if (( is_mode_partial )) && (( is_mode_regexp )); then
+    echo "\`--partial' and \`--regexp' are mutually exclusive" \
+    | batslib_decorate 'ERROR: refute_line' \
+    | fail
+    return $?
+  fi
+
+  # Arguments.
+  local -r unexpected="$1"
+
+  if (( is_mode_regexp == 1 )) && [[ '' =~ $unexpected ]] || (( $? == 2 )); then
+    echo "Invalid extended regular expression: \`$unexpected'" \
+    | batslib_decorate 'ERROR: refute_line' \
+    | fail
+    return $?
+  fi
+
+  # Matching.
+  if (( is_match_line )); then
+    # Specific line.
+    if (( is_mode_regexp )); then
+      if [[ ${lines[$idx]} =~ $unexpected ]]; then
+        batslib_print_kv_single 6 \
+        'index' "$idx" \
+        'regexp' "$unexpected" \
+        'line'  "${lines[$idx]}" \
+        | batslib_decorate 'regular expression should not match line' \
+        | fail
+      fi
+    elif (( is_mode_partial )); then
+      if [[ ${lines[$idx]} == *"$unexpected"* ]]; then
+        batslib_print_kv_single 9 \
+        'index'     "$idx" \
+        'substring' "$unexpected" \
+        'line'      "${lines[$idx]}" \
+        | batslib_decorate 'line should not contain substring' \
+        | fail
+      fi
+    else
+      if [[ ${lines[$idx]} == "$unexpected" ]]; then
+        batslib_print_kv_single 5 \
+        'index' "$idx" \
+        'line'  "${lines[$idx]}" \
+        | batslib_decorate 'line should differ' \
+        | fail
+      fi
+    fi
+  else
+    # Line contained in output.
+    if (( is_mode_regexp )); then
+      local -i idx
+      for (( idx = 0; idx < ${#lines[@]}; ++idx )); do
+        if [[ ${lines[$idx]} =~ $unexpected ]]; then
+          { local -ar single=( 'regexp' "$unexpected" 'index' "$idx" )
+            local -a may_be_multi=( 'output' "$output" )
+            local -ir width="$( batslib_get_max_single_line_key_width "${single[@]}" "${may_be_multi[@]}" )"
+            batslib_print_kv_single "$width" "${single[@]}"
+            if batslib_is_single_line "${may_be_multi[1]}"; then
+              batslib_print_kv_single "$width" "${may_be_multi[@]}"
+            else
+              may_be_multi[1]="$( printf '%s' "${may_be_multi[1]}" | batslib_prefix | batslib_mark '>' "$idx" )"
+              batslib_print_kv_multi "${may_be_multi[@]}"
+            fi
+          } \
+          | batslib_decorate 'no line should match the regular expression' \
+          | fail
+          return $?
+        fi
+      done
+    elif (( is_mode_partial )); then
+      local -i idx
+      for (( idx = 0; idx < ${#lines[@]}; ++idx )); do
+        if [[ ${lines[$idx]} == *"$unexpected"* ]]; then
+          { local -ar single=( 'substring' "$unexpected" 'index' "$idx" )
+            local -a may_be_multi=( 'output' "$output" )
+            local -ir width="$( batslib_get_max_single_line_key_width "${single[@]}" "${may_be_multi[@]}" )"
+            batslib_print_kv_single "$width" "${single[@]}"
+            if batslib_is_single_line "${may_be_multi[1]}"; then
+              batslib_print_kv_single "$width" "${may_be_multi[@]}"
+            else
+              may_be_multi[1]="$( printf '%s' "${may_be_multi[1]}" | batslib_prefix | batslib_mark '>' "$idx" )"
+              batslib_print_kv_multi "${may_be_multi[@]}"
+            fi
+          } \
+          | batslib_decorate 'no line should contain substring' \
+          | fail
+          return $?
+        fi
+      done
+    else
+      local -i idx
+      for (( idx = 0; idx < ${#lines[@]}; ++idx )); do
+        if [[ ${lines[$idx]} == "$unexpected" ]]; then
+          { local -ar single=( 'line' "$unexpected" 'index' "$idx" )
+            local -a may_be_multi=( 'output' "$output" )
+            local -ir width="$( batslib_get_max_single_line_key_width "${single[@]}" "${may_be_multi[@]}" )"
+            batslib_print_kv_single "$width" "${single[@]}"
+            if batslib_is_single_line "${may_be_multi[1]}"; then
+              batslib_print_kv_single "$width" "${may_be_multi[@]}"
+            else
+              may_be_multi[1]="$( printf '%s' "${may_be_multi[1]}" | batslib_prefix | batslib_mark '>' "$idx" )"
+              batslib_print_kv_multi "${may_be_multi[@]}"
+            fi
+          } \
+          | batslib_decorate 'line should not be in output' \
+          | fail
+          return $?
+        fi
+      done
+    fi
+  fi
+}
+
+refute_output() {
+  local -i is_mode_partial=0
+  local -i is_mode_regexp=0
+  local -i is_mode_empty=0
+  local -i use_stdin=0
+  : "${output?}"
+
+  # Handle options.
+  if (( $# == 0 )); then
+    is_mode_empty=1
+  fi
+
+  while (( $# > 0 )); do
+    case "$1" in
+    -p|--partial) is_mode_partial=1; shift ;;
+    -e|--regexp) is_mode_regexp=1; shift ;;
+    -|--stdin) use_stdin=1; shift ;;
+    --) shift; break ;;
+    *) break ;;
+    esac
+  done
+
+  if (( is_mode_partial )) && (( is_mode_regexp )); then
+    echo "\`--partial' and \`--regexp' are mutually exclusive" \
+    | batslib_decorate 'ERROR: refute_output' \
+    | fail
+    return $?
+  fi
+
+  # Arguments.
+  local unexpected
+  if (( use_stdin )); then
+    unexpected="$(cat -)"
+  else
+    unexpected="${1-}"
+  fi
+
+  if (( is_mode_regexp == 1 )) && [[ '' =~ $unexpected ]] || (( $? == 2 )); then
+    echo "Invalid extended regular expression: \`$unexpected'" \
+    | batslib_decorate 'ERROR: refute_output' \
+    | fail
+    return $?
+  fi
+
+  # Matching.
+  if (( is_mode_empty )); then
+    if [ -n "$output" ]; then
+      batslib_print_kv_single_or_multi 6 \
+      'output' "$output" \
+      | batslib_decorate 'output non-empty, but expected no output' \
+      | fail
+    fi
+  elif (( is_mode_regexp )); then
+    if [[ $output =~ $unexpected ]]; then
+      batslib_print_kv_single_or_multi 6 \
+      'regexp'  "$unexpected" \
+      'output' "$output" \
+      | batslib_decorate 'regular expression should not match output' \
+      | fail
+    fi
+  elif (( is_mode_partial )); then
+    if [[ $output == *"$unexpected"* ]]; then
+      batslib_print_kv_single_or_multi 9 \
+      'substring' "$unexpected" \
+      'output'    "$output" \
+      | batslib_decorate 'output should not contain substring' \
+      | fail
+    fi
+  else
+    if [[ $output == "$unexpected" ]]; then
+      batslib_print_kv_single_or_multi 6 \
+      'output' "$output" \
+      | batslib_decorate 'output equals, but it was expected to differ' \
+      | fail
+    fi
+  fi
+}
diff --git a/exercises/practice/bottle-song/bottle-song.awk b/exercises/practice/bottle-song/bottle-song.awk
new file mode 100644
index 0000000..be84599
--- /dev/null
+++ b/exercises/practice/bottle-song/bottle-song.awk
@@ -0,0 +1,8 @@
+# These variables are initialized on the command line (using '-v'):
+# - startBottles
+# - takeDown
+
+BEGIN {
+    print "Implement this solution" > "/dev/stderr"
+    exit 1
+}
diff --git a/exercises/practice/bottle-song/test-bottle-song.bats b/exercises/practice/bottle-song/test-bottle-song.bats
new file mode 100644
index 0000000..6fc109b
--- /dev/null
+++ b/exercises/practice/bottle-song/test-bottle-song.bats
@@ -0,0 +1,153 @@
+#!/usr/bin/env bats
+load bats-extra
+
+@test 'first_generic_verse' {
+    #[[ $BATS_RUN_SKIPPED == "true" ]] || skip
+    run gawk -f bottle-song.awk -v startBottles=10 -v takeDown=1
+
+    expected="Ten green bottles hanging on the wall,
+Ten green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be nine green bottles hanging on the wall."
+
+    assert_success
+    assert_output "$expected"
+}
+
+@test 'last_generic_verse' {
+    [[ $BATS_RUN_SKIPPED == "true" ]] || skip
+    run gawk -f bottle-song.awk -v startBottles=3 -v takeDown=1
+
+    expected="Three green bottles hanging on the wall,
+Three green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be two green bottles hanging on the wall."
+
+    assert_success
+    assert_output "$expected"
+}
+
+@test 'verse_with_2_bottles' {
+    [[ $BATS_RUN_SKIPPED == "true" ]] || skip
+    run gawk -f bottle-song.awk -v startBottles=2 -v takeDown=1
+
+    expected="Two green bottles hanging on the wall,
+Two green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be one green bottle hanging on the wall."
+
+    assert_success
+    assert_output "$expected"
+}
+
+@test 'verse_with_1_bottle' {
+    [[ $BATS_RUN_SKIPPED == "true" ]] || skip
+    run gawk -f bottle-song.awk -v startBottles=1 -v takeDown=1
+
+    expected="One green bottle hanging on the wall,
+One green bottle hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be no green bottles hanging on the wall."
+
+    assert_success
+    assert_output "$expected"
+}
+
+@test 'first_two_verses' {
+    [[ $BATS_RUN_SKIPPED == "true" ]] || skip
+    run gawk -f bottle-song.awk -v startBottles=10 -v takeDown=2
+
+    expected="Ten green bottles hanging on the wall,
+Ten green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be nine green bottles hanging on the wall.
+
+Nine green bottles hanging on the wall,
+Nine green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be eight green bottles hanging on the wall."
+
+    assert_success
+    assert_output "$expected"
+}
+
+@test 'last_three_verses' {
+    [[ $BATS_RUN_SKIPPED == "true" ]] || skip
+    run gawk -f bottle-song.awk -v startBottles=3 -v takeDown=3
+
+    expected="Three green bottles hanging on the wall,
+Three green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be two green bottles hanging on the wall.
+
+Two green bottles hanging on the wall,
+Two green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be one green bottle hanging on the wall.
+
+One green bottle hanging on the wall,
+One green bottle hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be no green bottles hanging on the wall."
+
+    assert_success
+    assert_output "$expected"
+}
+
+@test 'all_verses' {
+    [[ $BATS_RUN_SKIPPED == "true" ]] || skip
+    run gawk -f bottle-song.awk -v startBottles=10 -v takeDown=10
+
+    expected="Ten green bottles hanging on the wall,
+Ten green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be nine green bottles hanging on the wall.
+
+Nine green bottles hanging on the wall,
+Nine green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be eight green bottles hanging on the wall.
+
+Eight green bottles hanging on the wall,
+Eight green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be seven green bottles hanging on the wall.
+
+Seven green bottles hanging on the wall,
+Seven green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be six green bottles hanging on the wall.
+
+Six green bottles hanging on the wall,
+Six green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be five green bottles hanging on the wall.
+
+Five green bottles hanging on the wall,
+Five green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be four green bottles hanging on the wall.
+
+Four green bottles hanging on the wall,
+Four green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be three green bottles hanging on the wall.
+
+Three green bottles hanging on the wall,
+Three green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be two green bottles hanging on the wall.
+
+Two green bottles hanging on the wall,
+Two green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be one green bottle hanging on the wall.
+
+One green bottle hanging on the wall,
+One green bottle hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be no green bottles hanging on the wall."
+
+    assert_success
+    assert_output "$expected"
+}