Add save the cow exercise

config.json

@@ -556,6 +556,14 @@
           "string_transformation"
         ]
       },
+      {
+        "slug": "save-the-cow",
+        "name": "Save the Cow",
+        "uuid": "21b2a344-925e-427a-a2bb-69122df2ce61",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 3
+      },
       {
         "slug": "sieve",
         "name": "Sieve",

exercises/practice/save-the-cow/.docs/instructions.md

@@ -0,0 +1,7 @@
+# Instructions
+
+Implement the logic for a word-guessing game.
+
+A player tries to solve a secret word by guessing individual letters.
+They win if they reveal all the letters in the secret word.
+They lose if they make ten incorrect guesses before revealing the word.

exercises/practice/save-the-cow/.docs/introduction.md

@@ -0,0 +1,4 @@
+# Introduction
+
+Bessie the cow has wandered onto an alien spaceship.
+Guess the secret door code to bring her home before the ship blasts off.

exercises/practice/save-the-cow/.meta/config.json

@@ -0,0 +1,17 @@
+{
+  "authors": [
+    "resu-xuniL"
+  ],
+  "files": {
+    "solution": [
+      "save_the_cow.sh"
+    ],
+    "test": [
+      "save_the_cow.bats"
+    ],
+    "example": [
+      ".meta/example.sh"
+    ]
+  },
+  "blurb": "Implement a word-guessing game."
+}

exercises/practice/save-the-cow/.meta/example.sh

@@ -0,0 +1,41 @@
+#!/usr/bin/env bash
+
+guess() {
+    local word="$1"; shift
+    local -a guesses=( "$@" )
+    local state="Ongoing"
+    local remaining_failures=9
+    local masked_word=${word//?/_}
+    local i
+
+    for guess in "${guesses[@]}"; do
+        if [[ $state == "Win" ]]; then
+            echo "cannot guess after the game is won" >&2
+            exit 1
+        elif [[ $state == "Lose" ]]; then
+            echo "cannot guess after the game is lost" >&2
+            exit 1
+        fi
+
+        if [[ -n $guess && $word =~ $guess && ! $masked_word =~ $guess ]]; then
+            for (( i = 0; i < ${#word}; i++ )); do
+                if [[ ${word:i:1} == "$guess" ]]; then
+                    masked_word="${masked_word:0:i}${guess}${masked_word:i+1}"
+                fi
+            done
+            if [[ ! $masked_word =~ "_" ]]; then
+                state="Win"
+            fi
+        elif [[ -n $guess ]]; then
+            if (( remaining_failures == 0 )); then
+                state="Lose"
+            else
+                (( remaining_failures -- ))
+            fi
+        fi
+    done
+
+    printf "State: %s\nMasked word: %s\nRemaining failures: %s" "$state" "$masked_word" "$remaining_failures"
+}
+
+guess "$@"

exercises/practice/save-the-cow/.meta/template.j2

@@ -0,0 +1,21 @@
+{{ header }}
+{% for case in cases %}
+@test "{{ case["descriptions"] | join(": ") }}" {
+    {% if loop.first %}# {% endif %}[[ $BATS_RUN_SKIPPED == "true" ]] || skip
+    run bash {{ solution }} "{{ case["input"]["word"] }}" "{{ case["input"]["guesses"] | join('" "') }}"
+{%- if case["expect_error"] %}
+    assert_failure
+    assert_output "{{ case["expect_error_msg"] }}"
+{%- else %}
+    expected="$(cat << EXPECTED
+State: {{ case["expected"]["state"] }}
+Masked word: {{ case["expected"]["maskedWord"] }}
+Remaining failures: {{ case["expected"]["remainingFailures"] }}
+EXPECTED
+    )"
+
+    assert_success
+    assert_output "$expected"
+{%- endif %}
+}
+{% endfor %}

exercises/practice/save-the-cow/.meta/tests.toml

@@ -0,0 +1,40 @@
+# 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.
+
+[71d340f9-fc29-4826-872e-ad7d0b83dd98]
+description = "Initially 9 failures are allowed and no letters are guessed"
+
+[76759c24-8f1a-4fc8-9ffd-d6a1ff0cf03b]
+description = "After 10 failures the game is over"
+
+[d6f2e202-7857-46fb-b709-43a7f3f3b2de]
+description = "Losing with several correct guesses"
+
+[71bc0cda-2032-4637-80c8-fc8771124c08]
+description = "Feeding a correct letter removes underscores"
+
+[5b568a1c-867d-418f-97a8-7b6f8a7ca0a2]
+description = "Feeding a correct letter twice counts as a failure"
+
+[3d40f15b-0271-4c5d-b1a4-3e1f66ff221f]
+description = "Guessing a repeated letter reveals all instances"
+
+[11a86435-e401-4250-a26e-3b0d8c4049ad]
+description = "Getting all the letters right makes for a win"
+
+[b3d81876-84ee-45bb-b531-baa1b05b4709]
+description = "Winning on the last guess is still a win"
+
+[cf204398-5e9f-402f-8bff-42cb7cbbbda9]
+description = "Guessing after a lose is error"
+
+[c2ec5b3d-4923-4a0e-a485-6aa6e78c7ece]
+description = "Guessing after a win is error"