fix: add utility file for managing the regex

src/main/kotlin/it/nicolasfarabegoli/gradle/CommitRegex.kt

@@ -0,0 +1,35 @@
+package it.nicolasfarabegoli.gradle
+
+private val types = listOf("build", "chore", "ci", "docs", "feat", "fix", "perf", "refactor", "revert", "style", "test")
+
+fun buildRegex(listOfScopes: List<String> = emptyList()): Regex {
+    return if (listOfScopes.isEmpty()) {
+        "^(${types.joinToString("|")})(\\([a-z \\-]+\\))?!?: .+\$".toRegex()
+    } else {
+        "^(${types.joinToString("|")})\\((${listOfScopes.joinToString("|")})\\)?!?: .+\$".toRegex()
+    }
+}
+
+val scriptContent = """
+    #!/usr/bin/env bash
+
+    # Create a regex for a conventional commit.
+    conventional_commit_regex="{0}"
+
+    # Get the commit message (the parameter we're given is just the path to the
+    # temporary file which holds the message).
+    commit_message=${'$'}(cat "${'$'}1")
+
+    # Check the message, if we match, all good baby.
+    if [[ "${'$'}commit_message" =~ ${'$'}conventional_commit_regex ]]; then
+       echo -e "\e[32mCommit message meets Conventional Commit standards...\e[0m"
+       exit 0
+    fi
+
+    # Uh-oh, this is not a conventional commit, show an example and link to the spec.
+    echo -e "\e[31mThe commit message does not meet the Conventional Commit standard\e[0m"
+    echo "An example of a valid message is: "
+    echo "  feat(login): add the 'remember me' button"
+    echo "More details at: https://www.conventionalcommits.org/en/v1.0.0/#summary"
+    exit 1
+""".trimIndent()

src/test/kotlin/it/nicolasfarabegoli/gradle/CommitRegexKtTest.kt

@@ -0,0 +1,20 @@
+package it.nicolasfarabegoli.gradle
+
+import io.kotest.core.spec.style.WordSpec
+import io.kotest.matchers.shouldBe
+
+class CommitRegexKtTest : WordSpec({
+    "A commit message" should {
+        "admit any scope if no scopes are given" {
+            buildRegex().matches("feat(scope): foo bar") shouldBe true
+            buildRegex().matches("foo bar") shouldBe false
+            buildRegex().matches("feat: foo bar") shouldBe true
+        }
+        "not admit scopes not allowed" {
+            val scopes = listOf("scope1", "scope2", "scope3")
+            buildRegex(scopes).matches("feat(scope1): foo bar") shouldBe true
+            buildRegex(scopes).matches("feat: foo bar") shouldBe false
+            buildRegex(scopes).matches("feat(scope4): foo bar") shouldBe false
+        }
+    }
+})