murk_cli/
git.rs

1//! Git integration helpers (merge driver setup).
2
3use std::fs;
4use std::io::Write;
5use std::path::Path;
6use std::process::Command;
7
8/// The `.gitattributes` line that enables the merge driver.
9const GITATTRIBUTES_LINE: &str = "*.murk merge=murk";
10
11/// Git config keys for the merge driver.
12const GIT_CONFIG_MERGE_NAME: &str = "merge.murk.name";
13const GIT_CONFIG_MERGE_DRIVER: &str = "merge.murk.driver";
14
15/// A step completed during merge driver setup.
16#[derive(Debug, PartialEq, Eq)]
17pub enum MergeDriverSetupStep {
18    /// `.gitattributes` already contained the merge driver entry.
19    GitattributesAlreadyExists,
20    /// Appended the merge driver entry to an existing `.gitattributes`.
21    GitattributesAppended,
22    /// Created a new `.gitattributes` file with the merge driver entry.
23    GitattributesCreated,
24    /// Configured `git config merge.murk.*`.
25    GitConfigured,
26}
27
28/// Configure git to use murk's custom merge driver for `.murk` files.
29///
30/// 1. Ensures `.gitattributes` contains `*.murk merge=murk`.
31/// 2. Runs `git config merge.murk.name` and `git config merge.murk.driver`.
32///
33/// Returns the steps that were performed.
34pub fn setup_merge_driver() -> Result<Vec<MergeDriverSetupStep>, String> {
35    let mut steps = Vec::new();
36
37    // 1. Write .gitattributes entry.
38    let gitattributes = Path::new(".gitattributes");
39    let merge_line = GITATTRIBUTES_LINE;
40
41    crate::env::reject_symlink(gitattributes, ".gitattributes")?;
42
43    if gitattributes.exists() {
44        let contents = fs::read_to_string(gitattributes)
45            .map_err(|e| format!("reading .gitattributes: {e}"))?;
46        if contents.contains(merge_line) {
47            steps.push(MergeDriverSetupStep::GitattributesAlreadyExists);
48        } else {
49            let mut file = fs::OpenOptions::new()
50                .append(true)
51                .open(gitattributes)
52                .map_err(|e| format!("writing .gitattributes: {e}"))?;
53            writeln!(file, "{merge_line}").map_err(|e| format!("writing .gitattributes: {e}"))?;
54            steps.push(MergeDriverSetupStep::GitattributesAppended);
55        }
56    } else {
57        fs::write(gitattributes, format!("{merge_line}\n"))
58            .map_err(|e| format!("writing .gitattributes: {e}"))?;
59        steps.push(MergeDriverSetupStep::GitattributesCreated);
60    }
61
62    // 2. Configure git merge driver.
63    let configs = [
64        (GIT_CONFIG_MERGE_NAME, "murk vault merge"),
65        (GIT_CONFIG_MERGE_DRIVER, "murk merge-driver %O %A %B"),
66    ];
67    for (key, value) in &configs {
68        let status = Command::new("git")
69            .args(["config", key, value])
70            .status()
71            .map_err(|e| format!("running git config: {e}"))?;
72        if !status.success() {
73            return Err(format!("git config {key} failed (are you in a git repo?)"));
74        }
75    }
76    steps.push(MergeDriverSetupStep::GitConfigured);
77
78    Ok(steps)
79}
80
81#[cfg(test)]
82mod tests {
83    use super::*;
84    use crate::testutil::CWD_LOCK;
85
86    #[test]
87    fn setup_merge_driver_creates_gitattributes() {
88        let _lock = CWD_LOCK.lock().unwrap_or_else(|e| e.into_inner());
89        let dir = std::env::temp_dir().join("murk_test_git_setup");
90        let _ = std::fs::remove_dir_all(&dir);
91        std::fs::create_dir_all(&dir).unwrap();
92
93        // Init a git repo so git config works.
94        Command::new("git")
95            .args(["init"])
96            .current_dir(&dir)
97            .output()
98            .unwrap();
99
100        let original_dir = std::env::current_dir().unwrap();
101        std::env::set_current_dir(&dir).unwrap();
102
103        let steps = setup_merge_driver().unwrap();
104        assert!(steps.contains(&MergeDriverSetupStep::GitattributesCreated));
105        assert!(steps.contains(&MergeDriverSetupStep::GitConfigured));
106
107        let contents = std::fs::read_to_string(dir.join(".gitattributes")).unwrap();
108        assert!(contents.contains("*.murk merge=murk"));
109
110        std::env::set_current_dir(original_dir).unwrap();
111        std::fs::remove_dir_all(&dir).unwrap();
112    }
113
114    #[test]
115    fn setup_merge_driver_appends_gitattributes() {
116        let _lock = CWD_LOCK.lock().unwrap_or_else(|e| e.into_inner());
117        let dir = std::env::temp_dir().join("murk_test_git_append");
118        let _ = std::fs::remove_dir_all(&dir);
119        std::fs::create_dir_all(&dir).unwrap();
120
121        Command::new("git")
122            .args(["init"])
123            .current_dir(&dir)
124            .output()
125            .unwrap();
126
127        std::fs::write(dir.join(".gitattributes"), "*.txt text\n").unwrap();
128
129        let original_dir = std::env::current_dir().unwrap();
130        std::env::set_current_dir(&dir).unwrap();
131
132        let steps = setup_merge_driver().unwrap();
133        assert!(steps.contains(&MergeDriverSetupStep::GitattributesAppended));
134
135        let contents = std::fs::read_to_string(dir.join(".gitattributes")).unwrap();
136        assert!(contents.contains("*.txt text"));
137        assert!(contents.contains("*.murk merge=murk"));
138
139        std::env::set_current_dir(original_dir).unwrap();
140        std::fs::remove_dir_all(&dir).unwrap();
141    }
142
143    #[test]
144    fn setup_merge_driver_already_exists() {
145        let _lock = CWD_LOCK.lock().unwrap_or_else(|e| e.into_inner());
146        let dir = std::env::temp_dir().join("murk_test_git_exists");
147        let _ = std::fs::remove_dir_all(&dir);
148        std::fs::create_dir_all(&dir).unwrap();
149
150        Command::new("git")
151            .args(["init"])
152            .current_dir(&dir)
153            .output()
154            .unwrap();
155
156        std::fs::write(dir.join(".gitattributes"), "*.murk merge=murk\n").unwrap();
157
158        let original_dir = std::env::current_dir().unwrap();
159        std::env::set_current_dir(&dir).unwrap();
160
161        let steps = setup_merge_driver().unwrap();
162        assert!(steps.contains(&MergeDriverSetupStep::GitattributesAlreadyExists));
163
164        std::env::set_current_dir(original_dir).unwrap();
165        std::fs::remove_dir_all(&dir).unwrap();
166    }
167}
murk_cli/git.rs

murk_cli/
git.rs
