// Copyright Kitware, Inc.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

use derive_builder::Builder;
use git_checks_core::impl_prelude::*;
use itertools::Itertools;
use lazy_static::lazy_static;
use regex::Regex;

/// Check commit message subjects for invalid patterns.
///
/// Patterns which are checked for:
///   - overly long or short summary lines;
///   - work-in-progress messages;
///   - `fixup!` and `squash!` messages; and
///   - custom prefixes.
///
/// Commit messages which appear to have been auto generated by actions such as merging or
/// reverting commits will skip the summary line length limit (if enforced).
#[derive(Builder, Debug, Clone)]
#[builder(field(private))]
pub struct CommitSubject {
    /// The minimum length allowed for the summary line.
    ///
    /// Configuration: Optional
    /// Default: `8`
    #[builder(default = "8")]
    min_summary: usize,
    /// The maximum length allowed for the summary line.
    ///
    /// Configuration: Optional
    /// Default: `78`
    #[builder(default = "78")]
    max_summary: usize,

    /// Whether to deny work-in-progress commits or not.
    ///
    /// Commit messages which mention `WIP`, `wip`, or a few variants of `Draft` at the beginning
    /// of their commit messages are rejected since they are (nominally) incomplete.
    ///
    /// Configuration: Optional
    /// Default: `true`
    #[builder(default = "true")]
    check_work_in_progress: bool,

    /// Check for rebase commands
    ///
    /// Rebase commands include commits which begin with `fixup! `, `squash! `, or `amend! `. These
    /// subjects are used to indicate that the commit belongs somewhere else in the branch and
    /// should be completed before merging.
    ///
    /// Configuration: Optional
    /// Default: `true`
    #[builder(default = "true")]
    check_rebase_commands: bool,

    /// Check for suggestions applied through a hosting facility
    ///
    /// Some hosting services support applying suggestions for changes to a topic as a new commit.
    /// Enabling this option detects these subjects and rejects the commit as the code suggestion
    /// should be squashed back into the relevant commit.
    ///
    /// Configuration: Optional
    /// Default: `false`
    #[builder(default = "false")]
    check_suggestion_subjects: bool,

    #[builder(private)]
    #[builder(setter(name = "_tolerated_prefixes"))]
    #[builder(default)]
    tolerated_prefixes: Vec<Regex>,
    #[builder(private)]
    #[builder(setter(name = "_allowed_prefixes"))]
    #[builder(default)]
    allowed_prefixes: Vec<String>,
    #[builder(private)]
    #[builder(setter(name = "_disallowed_prefixes"))]
    #[builder(default)]
    disallowed_prefixes: Vec<String>,
}

lazy_static! {
    static ref SUGGESTION_SUBJECTS: Vec<Regex> = vec![
        // GitLab
        Regex::new(r#"Apply \d* suggestion\(s\) to \d* file\(s\)"#).unwrap(),
        // GitHub. Developers are asked for commit information, but this is the default for a
        // "batch" of suggestions.
        Regex::new("Apply suggestions from code review").unwrap(),
    ];
}

impl CommitSubjectBuilder {
    /// Tolerated prefixes for commits.
    ///
    /// The specified prefix patterns will be tolerated regardless of any configured
    /// allowed or disallowed prefixes.
    ///
    /// Configuration: Optional
    /// Default: `Vec::new()`
    pub fn tolerated_prefixes<I, P>(&mut self, patterns: I) -> &mut Self
    where
        I: IntoIterator<Item = P>,
        P: Into<Regex>,
    {
        self.tolerated_prefixes = Some(patterns.into_iter().map(Into::into).collect());
        self
    }

    /// Required prefixes for commits.
    ///
    /// The specified prefixes will be the only allowed prefixes on commit message subjects
    /// that do not match a tolerated pattern.
    ///
    /// Configuration: Optional
    /// Default: `Vec::new()`
    pub fn allowed_prefixes<I, P>(&mut self, prefixes: I) -> &mut Self
    where
        I: IntoIterator<Item = P>,
        P: Into<String>,
    {
        self.allowed_prefixes = Some(prefixes.into_iter().map(Into::into).collect());
        self
    }

    /// Forbidden prefixes for commits.
    ///
    /// The specified prefixes will be rejected on commit message subjects that do not
    /// also match a tolerated pattern.
    ///
    /// Configuration: Optional
    /// Default: `Vec::new()`
    pub fn disallowed_prefixes<I, P>(&mut self, prefixes: I) -> &mut Self
    where
        I: IntoIterator<Item = P>,
        P: Into<String>,
    {
        self.disallowed_prefixes = Some(prefixes.into_iter().map(Into::into).collect());
        self
    }
}

impl CommitSubject {
    /// Create a new builder.
    pub fn builder() -> CommitSubjectBuilder {
        CommitSubjectBuilder::default()
    }

    /// Whether the summary is generated or not.
    ///
    /// The commit summaries generated by `git merge` and `git revert` can be long, but since they
    /// are auto-generated, allow them.
    fn is_generated_subject(summary: &str) -> bool {
        summary.starts_with("Merge ") || summary.starts_with("Revert ")
    }
}

impl Default for CommitSubject {
    fn default() -> Self {
        CommitSubject {
            min_summary: 8,
            max_summary: 78,
            check_work_in_progress: true,
            check_rebase_commands: true,
            check_suggestion_subjects: false,
            tolerated_prefixes: Vec::new(),
            allowed_prefixes: Vec::new(),
            disallowed_prefixes: Vec::new(),
        }
    }
}

impl Check for CommitSubject {
    fn name(&self) -> &str {
        "commit-subject"
    }

    fn check(&self, _: &CheckGitContext, commit: &Commit) -> Result<CheckResult, Box<dyn Error>> {
        let mut result = CheckResult::new();
        let lines = commit.message.trim().lines().collect::<Vec<_>>();

        if lines.is_empty() {
            result.add_error(format!(
                "commit {} has an invalid commit subject; it is empty.",
                commit.sha1,
            ));
            return Ok(result);
        }

        let summary = &lines[0];
        let summary_len = summary.len();

        if summary_len < self.min_summary {
            result.add_error(format!(
                "commit {} has an invalid commit subject; the first line must be at least {} \
                 characters.",
                commit.sha1, self.min_summary,
            ));
        }

        let is_generated = Self::is_generated_subject(summary);
        if !is_generated && self.max_summary < summary_len {
            result.add_error(format!(
                "commit {} has an invalid commit subject; the first line must be no longer than \
                 {} characters.",
                commit.sha1, self.max_summary,
            ));
        }

        if lines.len() >= 2 {
            if lines.len() >= 2 && !lines[1].is_empty() {
                result.add_error(format!(
                    "commit {} has an invalid commit subject; the second line must be empty.",
                    commit.sha1,
                ));
            }

            if lines.len() == 2 {
                result.add_error(format!(
                    "commit {} has an invalid commit subject; it cannot be exactly two lines.",
                    commit.sha1,
                ));
            } else if lines[2].is_empty() {
                result.add_error(format!(
                    "commit {} has an invalid commit subject; the third line must not be empty.",
                    commit.sha1,
                ));
            }
        }

        const WIP_PREFIXES: &[&str] = &[
            "WIP", "wip", "Draft:", "draft:", "[Draft]", "[draft]", "(Draft)", "(draft)",
        ];

        if self.check_work_in_progress
            && WIP_PREFIXES
                .iter()
                .any(|prefix| summary.starts_with(prefix))
        {
            result.add_error(format!(
                "commit {} cannot be merged; it is marked as a work-in-progress (WIP).",
                commit.sha1,
            ));
        }

        if self.check_rebase_commands {
            if summary.starts_with("fixup! ") {
                result.add_error(format!(
                    "commit {} cannot be merged; it is marked as a fixup commit.",
                    commit.sha1,
                ));
            } else if summary.starts_with("squash! ") {
                result.add_error(format!(
                    "commit {} cannot be merged; it is marked as a commit to be squashed.",
                    commit.sha1,
                ));
            } else if summary.starts_with("amend! ") {
                result.add_error(format!(
                    "commit {} cannot be merged; it is marked as an amending commit.",
                    commit.sha1,
                ));
            }
        }

        if self.check_suggestion_subjects {
            for subject in SUGGESTION_SUBJECTS.iter() {
                if subject.is_match(summary) {
                    result.add_error(format!(
                        "commit {} cannot be merged; its commit summary appears to have been \
                         automatically generated by a suggestion application mechanism. Please \
                         squash the suggestion(s) into the relevant commit(s) using `git rebase`.",
                        commit.sha1,
                    ));
                }
            }
        }

        if !is_generated {
            let is_tolerated = self.tolerated_prefixes.iter().any(|regex| {
                regex
                    .find(summary)
                    .map(|found| found.start() == 0)
                    .unwrap_or(false)
            });
            if !is_tolerated {
                if !self.allowed_prefixes.is_empty() {
                    let is_ok = self
                        .allowed_prefixes
                        .iter()
                        .any(|prefix| summary.starts_with(prefix));
                    if !is_ok {
                        result.add_error(format!(
                            "commit {} cannot be merged; it must start with one of the following \
                             prefixes: `{}`.",
                            commit.sha1,
                            self.allowed_prefixes.iter().format("`, `"),
                        ));
                    }
                }

                let is_ok = self
                    .disallowed_prefixes
                    .iter()
                    .all(|prefix| !summary.starts_with(prefix));
                if !is_ok {
                    result.add_error(format!(
                        "commit {} cannot be merged; it cannot start with any of the following \
                         prefixes: `{}`.",
                        commit.sha1,
                        self.disallowed_prefixes.iter().format("`, `"),
                    ));
                }
            }
        }

        Ok(result)
    }
}

#[cfg(feature = "config")]
pub(crate) mod config {
    use git_checks_config::{register_checks, CommitCheckConfig, IntoCheck};
    use regex::Regex;
    use serde::de::{Deserializer, Error as SerdeError};
    use serde::Deserialize;
    #[cfg(test)]
    use serde_json::json;

    use crate::CommitSubject;

    #[derive(Debug)]
    struct RegexConfig(Regex);

    impl<'de> Deserialize<'de> for RegexConfig {
        fn deserialize<D>(deserializer: D) -> ::std::result::Result<Self, D::Error>
        where
            D: Deserializer<'de>,
        {
            let regex_str = <String as Deserialize>::deserialize(deserializer)?;
            let regex = Regex::new(&regex_str)
                .map_err(|err| D::Error::custom(format!("'{}': {}", regex_str, err)))?;
            Ok(RegexConfig(regex))
        }
    }

    impl From<RegexConfig> for Regex {
        fn from(regex_config: RegexConfig) -> Self {
            regex_config.0
        }
    }

    /// Configuration for the `CommitSubject` check.
    ///
    /// No configuration is necessary. The defaults are guided by common commit message guidelines.
    ///
    /// | Field | Type | Default |
    /// | ----- | ---- | ------- |
    /// | `min_summary` | positive integer | 8 |
    /// | `max_summary` | positive integer | 78 |
    /// | `check_work_in_progress` | boolean | true |
    /// | `check_rebase_commands` | boolean | true |
    /// | `check_suggestion_subjects` | boolean | false |
    ///
    /// The prefix configurations are lists of strings that are by default empty lists. The
    /// `tolerated_prefixes` key is interpreted as a list of regular expressions.
    ///
    /// This check is registered as a commit check with the name `"commit_subject".
    ///
    /// # Example
    ///
    /// ```json
    /// {
    ///     "min_summary": 8,
    ///     "max_summary": 78,
    ///
    ///     "check_work_in_progress": true,
    ///     "check_rebase_commands": true,
    ///     "check_suggestion_subjects": true,
    ///
    ///     "tolerated_prefixes": [
    ///         "regex"
    ///     ],
    ///     "allowed_prefixes": [
    ///         "literal"
    ///     ],
    ///     "disallowed_prefixes": [
    ///         "literal"
    ///     ]
    /// }
    /// ```
    #[derive(Deserialize, Debug)]
    pub struct CommitSubjectConfig {
        #[serde(default)]
        min_summary: Option<usize>,
        #[serde(default)]
        max_summary: Option<usize>,

        #[serde(default)]
        check_work_in_progress: Option<bool>,
        #[serde(default)]
        check_rebase_commands: Option<bool>,
        #[serde(default)]
        check_suggestion_subjects: Option<bool>,

        #[serde(default)]
        tolerated_prefixes: Option<Vec<RegexConfig>>,
        #[serde(default)]
        allowed_prefixes: Option<Vec<String>>,
        #[serde(default)]
        disallowed_prefixes: Option<Vec<String>>,
    }

    impl IntoCheck for CommitSubjectConfig {
        type Check = CommitSubject;

        fn into_check(self) -> Self::Check {
            let mut builder = CommitSubject::builder();

            if let Some(min_summary) = self.min_summary {
                builder.min_summary(min_summary);
            }

            if let Some(max_summary) = self.max_summary {
                builder.max_summary(max_summary);
            }

            if let Some(check_work_in_progress) = self.check_work_in_progress {
                builder.check_work_in_progress(check_work_in_progress);
            }

            if let Some(check_rebase_commands) = self.check_rebase_commands {
                builder.check_rebase_commands(check_rebase_commands);
            }

            if let Some(check_suggestion_subjects) = self.check_suggestion_subjects {
                builder.check_suggestion_subjects(check_suggestion_subjects);
            }

            if let Some(tolerated_prefixes) = self.tolerated_prefixes {
                builder.tolerated_prefixes(tolerated_prefixes);
            }

            if let Some(allowed_prefixes) = self.allowed_prefixes {
                builder.allowed_prefixes(allowed_prefixes);
            }

            if let Some(disallowed_prefixes) = self.disallowed_prefixes {
                builder.disallowed_prefixes(disallowed_prefixes);
            }

            builder
                .build()
                .expect("configuration mismatch for `CommitSubject`")
        }
    }

    register_checks! {
        CommitSubjectConfig {
            "commit_subject" => CommitCheckConfig,
        },
    }

    #[test]
    fn test_commit_subject_config_empty() {
        let json = json!({});
        let check: CommitSubjectConfig = serde_json::from_value(json).unwrap();

        assert_eq!(check.min_summary, None);
        assert_eq!(check.max_summary, None);
        assert_eq!(check.check_work_in_progress, None);
        assert_eq!(check.check_rebase_commands, None);
        assert_eq!(check.check_suggestion_subjects, None);
        assert!(check.tolerated_prefixes.is_none());
        assert_eq!(check.allowed_prefixes, None);
        assert_eq!(check.disallowed_prefixes, None);

        let check = check.into_check();

        assert_eq!(check.min_summary, 8);
        assert_eq!(check.max_summary, 78);
        assert!(check.check_work_in_progress);
        assert!(check.check_rebase_commands);
        assert!(!check.check_suggestion_subjects);
        assert!(check.tolerated_prefixes.is_empty());
        itertools::assert_equal(&check.allowed_prefixes, &[] as &[&str]);
        itertools::assert_equal(&check.disallowed_prefixes, &[] as &[&str]);
    }

    #[test]
    fn test_commit_subject_config_all_fields() {
        let exp_tprefix: String = "tolerated".into();
        let exp_aprefix: String = "allowed".into();
        let exp_dprefix: String = "disallowed".into();
        let json = json!({
            "min_summary": 1,
            "max_summary": 100,
            "check_work_in_progress": false,
            "check_rebase_commands": false,
            "check_suggestion_subjects": true,
            "tolerated_prefixes": [exp_tprefix],
            "allowed_prefixes": [exp_aprefix],
            "disallowed_prefixes": [exp_dprefix],
        });
        let check: CommitSubjectConfig = serde_json::from_value(json).unwrap();

        assert_eq!(check.min_summary, Some(1));
        assert_eq!(check.max_summary, Some(100));
        assert_eq!(check.check_work_in_progress, Some(false));
        assert_eq!(check.check_rebase_commands, Some(false));
        assert_eq!(check.check_suggestion_subjects, Some(true));
        itertools::assert_equal(
            check
                .tolerated_prefixes
                .as_ref()
                .unwrap()
                .iter()
                .map(|re| re.0.as_str()),
            &[exp_tprefix.clone()],
        );
        itertools::assert_equal(&check.allowed_prefixes, &Some([exp_aprefix.clone()]));
        itertools::assert_equal(&check.disallowed_prefixes, &Some([exp_dprefix.clone()]));

        let check = check.into_check();

        assert_eq!(check.min_summary, 1);
        assert_eq!(check.max_summary, 100);
        assert!(!check.check_work_in_progress);
        assert!(!check.check_rebase_commands);
        assert!(check.check_suggestion_subjects);
        itertools::assert_equal(
            check.tolerated_prefixes.iter().map(|re| re.as_str()),
            &[exp_tprefix],
        );
        itertools::assert_equal(&check.allowed_prefixes, &[exp_aprefix]);
        itertools::assert_equal(&check.disallowed_prefixes, &[exp_dprefix]);
    }
}

#[cfg(test)]
mod tests {
    use git_checks_core::Check;
    use regex::Regex;

    use crate::test::*;
    use crate::CommitSubject;

    const BAD_TOPIC: &str = "891db15952303d4f18ca23070c1bf054bc51a15c";

    #[test]
    fn test_commit_subject_builder_default() {
        assert!(CommitSubject::builder().build().is_ok());
    }

    #[test]
    fn test_commit_subject_name_commit() {
        let check = CommitSubject::default();
        assert_eq!(Check::name(&check), "commit-subject");
    }

    #[test]
    fn test_commit_subject() {
        let check = CommitSubject::default();
        let result = run_check("test_commit_subject", BAD_TOPIC, check);
        test_result_errors(result, &[
            "commit 234de3c3f17ab29f0b7644ae96242e31a3dd634c has an invalid commit subject; the \
             first line must be at least 8 characters.",
            "commit 1afc6b3584580488917fc61aa5e5298e98583805 has an invalid commit subject; the \
             first line must be no longer than 78 characters.",
            "commit b1ca628043ed78625551420e2dbbd8cf74fde2c4 has an invalid commit subject; the \
             second line must be empty.",
            "commit b1ca628043ed78625551420e2dbbd8cf74fde2c4 has an invalid commit subject; it \
             cannot be exactly two lines.",
            "commit 3a6fe6d56fbf11c667b6c88bdd7d851a8dcac0b1 has an invalid commit subject; the \
             second line must be empty.",
            "commit 3a6fe6d56fbf11c667b6c88bdd7d851a8dcac0b1 has an invalid commit subject; the \
             third line must not be empty.",
            "commit e478f630b586e331753477eba88059d644927be8 cannot be merged; it is marked as a \
             work-in-progress (WIP).",
            "commit 9039b9a4813fa019229e960033fe1ae8514a0c8e cannot be merged; it is marked as a \
             work-in-progress (WIP).",
            "commit 11dbbbff3f32445d74d1a8d96df0a49381c81ba0 cannot be merged; it is marked as a \
             work-in-progress (WIP).",
            "commit 54d673ff559a72ce6343bd9526a950d79034b24e cannot be merged; it is marked as a \
             fixup commit.",
            "commit 5f7284fe1599265c90550b681a4bf0763bc1de21 cannot be merged; it is marked as a \
             commit to be squashed.",
            "commit c4a9d2f34a687134e0d5d47ff576d34966381f56 has an invalid commit subject; it is \
             empty.",
            "commit 12b564db852a80190950caf5b363a4939b822730 cannot be merged; it is marked as an \
             amending commit.",
        ]);
    }

    #[test]
    fn test_commit_subject_with_suggestions() {
        let check = CommitSubject::builder()
            .check_work_in_progress(false)
            .check_rebase_commands(false)
            .check_suggestion_subjects(true)
            .build()
            .unwrap();
        let result = run_check("test_commit_subject_with_suggestions", BAD_TOPIC, check);
        test_result_errors(result, &[
            "commit 234de3c3f17ab29f0b7644ae96242e31a3dd634c has an invalid commit subject; the \
             first line must be at least 8 characters.",
            "commit 1afc6b3584580488917fc61aa5e5298e98583805 has an invalid commit subject; the \
             first line must be no longer than 78 characters.",
            "commit b1ca628043ed78625551420e2dbbd8cf74fde2c4 has an invalid commit subject; the \
             second line must be empty.",
            "commit b1ca628043ed78625551420e2dbbd8cf74fde2c4 has an invalid commit subject; it \
             cannot be exactly two lines.",
            "commit 3a6fe6d56fbf11c667b6c88bdd7d851a8dcac0b1 has an invalid commit subject; the \
             second line must be empty.",
            "commit 3a6fe6d56fbf11c667b6c88bdd7d851a8dcac0b1 has an invalid commit subject; the \
             third line must not be empty.",
            "commit c4a9d2f34a687134e0d5d47ff576d34966381f56 has an invalid commit subject; it is \
             empty.",
            "commit c52a84631f35561043cb7cca6c136f94bd9fc757 cannot be merged; its commit summary \
             appears to have been automatically generated by a suggestion application mechanism. \
             Please squash the suggestion(s) into the relevant commit(s) using `git rebase`.",
            "commit 891db15952303d4f18ca23070c1bf054bc51a15c cannot be merged; its commit summary \
             appears to have been automatically generated by a suggestion application mechanism. \
             Please squash the suggestion(s) into the relevant commit(s) using `git rebase`.",
        ]);
    }

    #[test]
    fn test_commit_subject_allowed_prefixes() {
        let check = CommitSubject::builder()
            .check_work_in_progress(false)
            .check_rebase_commands(false)
            .allowed_prefixes(["commit message "].iter().cloned())
            .build()
            .unwrap();
        let result = run_check("test_commit_subject_allowed_prefixes", BAD_TOPIC, check);
        test_result_errors(result, &[
            "commit 234de3c3f17ab29f0b7644ae96242e31a3dd634c has an invalid commit subject; the \
             first line must be at least 8 characters.",
            "commit 234de3c3f17ab29f0b7644ae96242e31a3dd634c cannot be merged; it must start with one of the following prefixes: `commit message `.",
            "commit 1afc6b3584580488917fc61aa5e5298e98583805 has an invalid commit subject; the \
             first line must be no longer than 78 characters.",
            "commit b1ca628043ed78625551420e2dbbd8cf74fde2c4 has an invalid commit subject; the \
             second line must be empty.",
            "commit b1ca628043ed78625551420e2dbbd8cf74fde2c4 has an invalid commit subject; it \
             cannot be exactly two lines.",
            "commit 3a6fe6d56fbf11c667b6c88bdd7d851a8dcac0b1 has an invalid commit subject; the \
             second line must be empty.",
            "commit 3a6fe6d56fbf11c667b6c88bdd7d851a8dcac0b1 has an invalid commit subject; the \
             third line must not be empty.",
            "commit e478f630b586e331753477eba88059d644927be8 cannot be merged; it must start with \
             one of the following prefixes: `commit message `.",
            "commit 9039b9a4813fa019229e960033fe1ae8514a0c8e cannot be merged; it must start with \
             one of the following prefixes: `commit message `.",
            "commit 11dbbbff3f32445d74d1a8d96df0a49381c81ba0 cannot be merged; it must start with \
             one of the following prefixes: `commit message `.",
            "commit 54d673ff559a72ce6343bd9526a950d79034b24e cannot be merged; it must start with \
             one of the following prefixes: `commit message `.",
            "commit 5f7284fe1599265c90550b681a4bf0763bc1de21 cannot be merged; it must start with \
             one of the following prefixes: `commit message `.",
            "commit c4a9d2f34a687134e0d5d47ff576d34966381f56 has an invalid commit subject; it is \
             empty.",
            "commit 12b564db852a80190950caf5b363a4939b822730 cannot be merged; it must start with \
             one of the following prefixes: `commit message `.",
            "commit c52a84631f35561043cb7cca6c136f94bd9fc757 cannot be merged; it must start with \
             one of the following prefixes: `commit message `.",
            "commit 891db15952303d4f18ca23070c1bf054bc51a15c cannot be merged; it must start with \
             one of the following prefixes: `commit message `.",
        ]);
    }

    #[test]
    fn test_commit_subject_disallowed_prefixes() {
        let check = CommitSubject::builder()
            .check_work_in_progress(false)
            .check_rebase_commands(false)
            .disallowed_prefixes(["commit message "].iter().cloned())
            .build()
            .unwrap();
        let result = run_check("test_commit_subject_disallowed_prefixes", BAD_TOPIC, check);
        test_result_errors(result, &[
            "commit 234de3c3f17ab29f0b7644ae96242e31a3dd634c has an invalid commit subject; the \
             first line must be at least 8 characters.",
            "commit 1afc6b3584580488917fc61aa5e5298e98583805 has an invalid commit subject; the \
             first line must be no longer than 78 characters.",
            "commit 1afc6b3584580488917fc61aa5e5298e98583805 cannot be merged; it cannot start \
             with any of the following prefixes: `commit message `.",
            "commit b1ca628043ed78625551420e2dbbd8cf74fde2c4 has an invalid commit subject; the \
             second line must be empty.",
            "commit b1ca628043ed78625551420e2dbbd8cf74fde2c4 has an invalid commit subject; it \
             cannot be exactly two lines.",
            "commit b1ca628043ed78625551420e2dbbd8cf74fde2c4 cannot be merged; it cannot start \
             with any of the following prefixes: `commit message `.",
            "commit 3a6fe6d56fbf11c667b6c88bdd7d851a8dcac0b1 has an invalid commit subject; the \
             second line must be empty.",
            "commit 3a6fe6d56fbf11c667b6c88bdd7d851a8dcac0b1 has an invalid commit subject; the \
             third line must not be empty.",
            "commit 3a6fe6d56fbf11c667b6c88bdd7d851a8dcac0b1 cannot be merged; it cannot start \
             with any of the following prefixes: `commit message `.",
            "commit c4a9d2f34a687134e0d5d47ff576d34966381f56 has an invalid commit subject; it is \
             empty.",
        ]);
    }

    #[test]
    fn test_commit_subject_tolerated_prefixes() {
        let check = CommitSubject::builder()
            .check_work_in_progress(false)
            .check_rebase_commands(false)
            .tolerated_prefixes(
                [
                    "^(commit message )",
                    "^([Ww][Ii][Pp]|fixup|squash|amend)",
                    "Apply",
                    // Intentionally match the middle of commit 234de3c3f's subject line
                    // to verify that the line "short" is not a tolerated prefix.
                    "hort",
                ]
                .iter()
                .map(|patt| Regex::new(patt).unwrap()),
            )
            .allowed_prefixes(["allowed prefix "].iter().cloned())
            .disallowed_prefixes(["commit message "].iter().cloned())
            .build()
            .unwrap();
        let result = run_check("test_commit_subject_tolerated_prefixes", BAD_TOPIC, check);
        test_result_errors(
            result,
            &[
                "commit 234de3c3f17ab29f0b7644ae96242e31a3dd634c has an invalid commit subject; \
                 the first line must be at least 8 characters.",
                "commit 234de3c3f17ab29f0b7644ae96242e31a3dd634c cannot be merged; it must start \
                 with one of the following prefixes: `allowed prefix `.",
                "commit 1afc6b3584580488917fc61aa5e5298e98583805 has an invalid commit subject; \
                 the first line must be no longer than 78 characters.",
                "commit b1ca628043ed78625551420e2dbbd8cf74fde2c4 has an invalid commit subject; \
                 the second line must be empty.",
                "commit b1ca628043ed78625551420e2dbbd8cf74fde2c4 has an invalid commit subject; \
                 it cannot be exactly two lines.",
                "commit 3a6fe6d56fbf11c667b6c88bdd7d851a8dcac0b1 has an invalid commit subject; \
                 the second line must be empty.",
                "commit 3a6fe6d56fbf11c667b6c88bdd7d851a8dcac0b1 has an invalid commit subject; \
                 the third line must not be empty.",
                "commit c4a9d2f34a687134e0d5d47ff576d34966381f56 has an invalid commit subject; \
                 it is empty.",
            ],
        );
    }
}