file_generator.rs

use std::cmp::Ordering;

use super::{Entry, Mapper};

pub struct FileGenerator {
    pub mappers: Vec<Box<dyn Mapper>>,
}

impl FileGenerator {
    pub fn generate_file(&self) -> String {
        let mut lines: Vec<String> = Vec::new();
        lines.append(&mut Self::disclaimer());

        for mapper in &self.mappers {
            if mapper.entries().is_empty() {
                continue;
            }

            lines.push(format!("# {}", mapper.name()));
            lines.append(&mut Self::to_sorted_lines(&mapper.entries()));
            lines.push("".to_owned());
        }

        lines.join("\n")
    }

    pub fn disclaimer() -> Vec<String> {
        [
            "# STOP! - DO NOT EDIT THIS FILE MANUALLY",
            "# This file was automatically generated by \"bin/codeownership validate\".",
            "#",
            "# CODEOWNERS is used for GitHub to suggest code/file owners to various GitHub",
            "# teams. This is useful when developers create Pull Requests since the",
            "# code/file owner is notified. Reference GitHub docs for more details:",
            "# https://help.github.com/en/articles/about-code-owners",
            "",
            "",
        ]
        .iter()
        .map(|line| line.to_string())
        .collect()
    }

    fn to_sorted_lines(entries: &[Entry]) -> Vec<String> {
        let mut lines: Vec<String> = entries.iter().map(|entry| entry.to_row()).collect();
        lines.sort_by(compare_lines);
        lines
    }
}

pub fn compare_lines(a: &String, b: &String) -> Ordering {
    if let Some((prefix, _)) = a.split_once("**") {
        if b.starts_with(prefix) {
            return Ordering::Less;
        }
    }
    if let Some((prefix, _)) = b.split_once("**") {
        if a.starts_with(prefix) {
            return Ordering::Greater;
        }
    }
    a.cmp(b)
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_to_sorted_lines_with_special_characters() {
        // The `(` character is less than `*` in the default sort order.
        let mut illustrate_issue = vec!["*".to_string(), "(".to_string()];
        illustrate_issue.sort();
        assert_eq!(illustrate_issue, vec!["(".to_string(), "*".to_string()]);

        let entries = vec![
            Entry {
                // Problem is when a dir name starts with `(`.
                path: "directory/owner/(my_folder)/**/**".to_string(),
                github_team: "@foo".to_string(),
                team_name: "footeam".to_string(),
                disabled: false,
            },
            Entry {
                // Another example of a dir starting with `(`.
                path: "directory/owner/(my_folder)/without_glob".to_string(),
                github_team: "@zoo".to_string(),
                team_name: "zooteam".to_string(),
                disabled: false,
            },
            Entry {
                // And is compared to a glob that starts with `*`.
                path: "directory/owner/**".to_string(),
                github_team: "@bar".to_string(),
                team_name: "barteam".to_string(),
                disabled: false,
            },
            Entry {
                path: "directory/owner/my_folder/**".to_string(),
                github_team: "@baz".to_string(),
                team_name: "bazteam".to_string(),
                disabled: false,
            },
            Entry {
                path: "directory/**".to_string(),
                github_team: "@bop".to_string(),
                team_name: "bopteam".to_string(),
                disabled: false,
            },
        ];
        let sorted = FileGenerator::to_sorted_lines(&entries);
        assert_eq!(
            sorted,
            vec![
                "/directory/** @bop",
                "/directory/owner/** @bar",
                "/directory/owner/(my_folder)/**/** @foo",
                "/directory/owner/(my_folder)/without_glob @zoo",
                "/directory/owner/my_folder/** @baz"
            ]
        );
    }

    #[test]
    fn test_basic_sorting() {
        let entries = vec![
            Entry {
                path: "b_directory/owner/**".to_string(),
                github_team: "@bar".to_string(),
                team_name: "barteam".to_string(),
                disabled: false,
            },
            Entry {
                path: "a_directory/owner/**".to_string(),
                github_team: "@foo".to_string(),
                team_name: "footeam".to_string(),
                disabled: false,
            },
        ];
        let sorted = FileGenerator::to_sorted_lines(&entries);
        assert_eq!(sorted, vec!["/a_directory/owner/** @foo", "/b_directory/owner/** @bar"]);
    }

    #[test]
    fn test_sorting_with_mixed_case() {
        let entries = vec![
            Entry {
                path: "directory/Owner/**".to_string(),
                github_team: "@bar".to_string(),
                team_name: "barteam".to_string(),
                disabled: false,
            },
            Entry {
                path: "directory/owner/**".to_string(),
                github_team: "@foo".to_string(),
                team_name: "footeam".to_string(),
                disabled: false,
            },
        ];
        let sorted = FileGenerator::to_sorted_lines(&entries);
        assert_eq!(sorted, vec!["/directory/Owner/** @bar", "/directory/owner/** @foo"]);
    }

    #[test]
    fn test_sorting_with_numbers() {
        let entries = vec![
            Entry {
                path: "directory/owner1/**".to_string(),
                github_team: "@foo".to_string(),
                team_name: "footeam".to_string(),
                disabled: false,
            },
            Entry {
                path: "directory/owner2/**".to_string(),
                github_team: "@bar".to_string(),
                team_name: "barteam".to_string(),
                disabled: false,
            },
        ];
        let sorted = FileGenerator::to_sorted_lines(&entries);
        assert_eq!(sorted, vec!["/directory/owner1/** @foo", "/directory/owner2/** @bar"]);
    }

    #[test]
    fn test_sorting_with_special_characters() {
        let entries = vec![
            Entry {
                path: "directory/owner-1/**".to_string(),
                github_team: "@foo".to_string(),
                team_name: "footeam".to_string(),
                disabled: false,
            },
            Entry {
                path: "directory/owner_2/**".to_string(),
                github_team: "@bar".to_string(),
                team_name: "barteam".to_string(),
                disabled: false,
            },
        ];
        let sorted = FileGenerator::to_sorted_lines(&entries);
        assert_eq!(sorted, vec!["/directory/owner-1/** @foo", "/directory/owner_2/** @bar"]);
    }
}