Set Fossil ignore and clean settings locally

Previously, the Fossil extension for `cargo new` would call `fossil
settings [...]` in order to configure the created repository to ignore
and allow cleaning the `target` build directory. However, as #9449
shows, it is ran from the CWD, which is probably outside of the repo,
therefore it modifies global settings instead of local ones. This aims
to fix that by writing the settings to local versioned files as the
issue recommends.

Signed-off-by: Paul Mabileau <paulmabileau@hotmail.fr>

src/cargo/ops/cargo_new.rs

@@ -517,6 +517,8 @@ struct IgnoreList {
     ignore: Vec<String>,
     /// mercurial formatted entries
     hg_ignore: Vec<String>,
+    /// Fossil-formatted entries.
+    fossil_ignore: Vec<String>,
 }
 
 impl IgnoreList {
@@ -525,22 +527,25 @@ impl IgnoreList {
         IgnoreList {
             ignore: Vec::new(),
             hg_ignore: Vec::new(),
+            fossil_ignore: Vec::new(),
         }
     }
 
-    /// add a new entry to the ignore list. Requires two arguments with the
-    /// entry in two different formats. One for "git style" entries and one for
-    /// "mercurial like" entries.
-    fn push(&mut self, ignore: &str, hg_ignore: &str) {
+    /// Add a new entry to the ignore list. Requires three arguments with the
+    /// entry in possibly three different formats. One for "git style" entries,
+    /// one for "mercurial style" entries and one for "fossil style" entries.
+    fn push(&mut self, ignore: &str, hg_ignore: &str, fossil_ignore: &str) {
         self.ignore.push(ignore.to_string());
         self.hg_ignore.push(hg_ignore.to_string());
+        self.fossil_ignore.push(fossil_ignore.to_string());
     }
 
     /// Return the correctly formatted content of the ignore file for the given
     /// version control system as `String`.
     fn format_new(&self, vcs: VersionControl) -> String {
         let ignore_items = match vcs {
             VersionControl::Hg => &self.hg_ignore,
+            VersionControl::Fossil => &self.fossil_ignore,
             _ => &self.ignore,
         };
 
@@ -557,20 +562,30 @@ impl IgnoreList {
 
         let ignore_items = match vcs {
             VersionControl::Hg => &self.hg_ignore,
+            VersionControl::Fossil => &self.fossil_ignore,
             _ => &self.ignore,
         };
 
-        let mut out = "\n\n# Added by cargo\n".to_string();
-        if ignore_items
-            .iter()
-            .any(|item| existing_items.contains(item))
-        {
-            out.push_str("#\n# already existing elements were commented out\n");
+        let mut out = String::new();
+
+        // Fossil does not support `#` comments.
+        if vcs != VersionControl::Fossil {
+            out.push_str("\n\n# Added by cargo\n");
+            if ignore_items
+                .iter()
+                .any(|item| existing_items.contains(item))
+            {
+                out.push_str("#\n# already existing elements were commented out\n");
+            }
+            out.push('\n');
         }
-        out.push('\n');
 
         for item in ignore_items {
             if existing_items.contains(item) {
+                if vcs == VersionControl::Fossil {
+                    // Just merge for Fossil.
+                    continue;
+                }
                 out.push('#');
             }
             out.push_str(item);
@@ -584,30 +599,35 @@ impl IgnoreList {
 /// Writes the ignore file to the given directory. If the ignore file for the
 /// given vcs system already exists, its content is read and duplicate ignore
 /// file entries are filtered out.
-fn write_ignore_file(
-    base_path: &Path,
-    list: &IgnoreList,
-    vcs: VersionControl,
-) -> CargoResult<String> {
-    let fp_ignore = match vcs {
-        VersionControl::Git => base_path.join(".gitignore"),
-        VersionControl::Hg => base_path.join(".hgignore"),
-        VersionControl::Pijul => base_path.join(".ignore"),
-        VersionControl::Fossil => return Ok("".to_string()),
-        VersionControl::NoVcs => return Ok("".to_string()),
-    };
+fn write_ignore_file(base_path: &Path, list: &IgnoreList, vcs: VersionControl) -> CargoResult<()> {
+    // Fossil only supports project-level settings in a dedicated subdirectory.
+    if vcs == VersionControl::Fossil {
+        paths::create_dir_all(base_path.join(".fossil-settings"))?;
+    }
 
-    let ignore: String = match paths::open(&fp_ignore) {
-        Err(err) => match err.downcast_ref::<std::io::Error>() {
-            Some(io_err) if io_err.kind() == ErrorKind::NotFound => list.format_new(vcs),
-            _ => return Err(err),
-        },
-        Ok(file) => list.format_existing(BufReader::new(file), vcs),
-    };
+    for fp_ignore in match vcs {
+        VersionControl::Git => vec![base_path.join(".gitignore")],
+        VersionControl::Hg => vec![base_path.join(".hgignore")],
+        VersionControl::Pijul => vec![base_path.join(".ignore")],
+        // Fossil has a cleaning functionality configured in a separate file.
+        VersionControl::Fossil => vec![
+            base_path.join(".fossil-settings/ignore-glob"),
+            base_path.join(".fossil-settings/clean-glob"),
+        ],
+        VersionControl::NoVcs => return Ok(()),
+    } {
+        let ignore: String = match paths::open(&fp_ignore) {
+            Err(err) => match err.downcast_ref::<std::io::Error>() {
+                Some(io_err) if io_err.kind() == ErrorKind::NotFound => list.format_new(vcs),
+                _ => return Err(err),
+            },
+            Ok(file) => list.format_existing(BufReader::new(file), vcs),
+        };
 
-    paths::append(&fp_ignore, ignore.as_bytes())?;
+        paths::append(&fp_ignore, ignore.as_bytes())?;
+    }
 
-    Ok(ignore)
+    Ok(())
 }
 
 /// Initializes the correct VCS system based on the provided config.
@@ -650,12 +670,12 @@ fn mk(config: &Config, opts: &MkOptions<'_>) -> CargoResult<()> {
     let name = opts.name;
     let cfg = config.get::<CargoNewConfig>("cargo-new")?;
 
-    // Using the push method with two arguments ensures that the entries for
-    // both `ignore` and `hgignore` are in sync.
+    // Using the push method with multiple arguments ensures that the entries
+    // for all mutually-incompatible VCS in terms of syntax are in sync.
     let mut ignore = IgnoreList::new();
-    ignore.push("/target", "^target/");
+    ignore.push("/target", "^target/", "target");
     if !opts.bin {
-        ignore.push("Cargo.lock", "glob:Cargo.lock");
+        ignore.push("Cargo.lock", "glob:Cargo.lock", "Cargo.lock,*/Cargo.lock");
     }
 
     let vcs = opts.version_control.unwrap_or_else(|| {

src/cargo/util/vcs.rs

@@ -95,21 +95,6 @@ impl FossilRepo {
             .arg(db_fname)
             .exec()?;
 
-        // set `target` as ignoreable and cleanable
-        ProcessBuilder::new("fossil")
-            .cwd(cwd)
-            .arg("settings")
-            .arg("ignore-glob")
-            .arg("target")
-            .exec()?;
-
-        ProcessBuilder::new("fossil")
-            .cwd(cwd)
-            .arg("settings")
-            .arg("clean-glob")
-            .arg("target")
-            .exec()?;
-
         Ok(FossilRepo)
     }
 }