git_hosting_providers: Add support for Chromium repositories (#24881)

Add an implementation of GitHostingProvider for repositories hosted on
https://chromium.googlesource.com. Pull requests target the Gerrit
instance at https://chromium-review.googlesource.com and avatar images
are fetched using the Gerrit REST API.

<img width="513" alt="Screenshot 2025-02-20 at 6 43 37 PM"
src="https://github.com/user-attachments/assets/867af988-594d-45ea-8482-e40517443c73"
/>

<img width="511" alt="Screenshot 2025-02-20 at 6 43 51 PM"
src="https://github.com/user-attachments/assets/1d412904-048d-4a2d-8494-0837e75f8d61"
/>

Release Notes:

- Added support for repositories hosted on `chromium.googlesource.com`
for Git blames and permalinks.

---------

Co-authored-by: Marshall Bowers <git@maxdeviant.com>

crates/git_hosting_providers/src/git_hosting_providers.rs

@@ -12,6 +12,7 @@ pub use crate::providers::*;
 pub fn init(cx: &App) {
     let provider_registry = GitHostingProviderRegistry::global(cx);
     provider_registry.register_hosting_provider(Arc::new(Bitbucket));
+    provider_registry.register_hosting_provider(Arc::new(Chromium));
     provider_registry.register_hosting_provider(Arc::new(Codeberg));
     provider_registry.register_hosting_provider(Arc::new(Gitee));
     provider_registry.register_hosting_provider(Arc::new(Github));

crates/git_hosting_providers/src/providers.rs

@@ -1,4 +1,5 @@
 mod bitbucket;
+mod chromium;
 mod codeberg;
 mod gitee;
 mod github;
@@ -6,6 +7,7 @@ mod gitlab;
 mod sourcehut;
 
 pub use bitbucket::*;
+pub use chromium::*;
 pub use codeberg::*;
 pub use gitee::*;
 pub use github::*;

crates/git_hosting_providers/src/providers/chromium.rs

@@ -0,0 +1,302 @@
+use std::str::FromStr;
+use std::sync::{Arc, LazyLock};
+
+use anyhow::{bail, Context, Result};
+use async_trait::async_trait;
+use futures::AsyncReadExt;
+use git::{
+    BuildCommitPermalinkParams, BuildPermalinkParams, GitHostingProvider, ParsedGitRemote,
+    PullRequest, RemoteUrl,
+};
+use gpui::SharedString;
+use http_client::{AsyncBody, HttpClient, HttpRequestExt, Request};
+use regex::Regex;
+use serde::Deserialize;
+use url::Url;
+
+const CHROMIUM_REVIEW_URL: &str = "https://chromium-review.googlesource.com";
+
+/// Parses Gerrit URLs like
+/// https://chromium-review.googlesource.com/c/chromium/src/+/3310961.
+fn pull_request_regex() -> &'static Regex {
+    static PULL_REQUEST_NUMBER_REGEX: LazyLock<Regex> = LazyLock::new(|| {
+        Regex::new(&format!(
+            r#"Reviewed-on: ({CHROMIUM_REVIEW_URL}/c/(.*)/\+/(\d+))"#
+        ))
+        .unwrap()
+    });
+    &PULL_REQUEST_NUMBER_REGEX
+}
+
+/// https://gerrit-review.googlesource.com/Documentation/rest-api-changes.html
+#[derive(Debug, Deserialize)]
+struct ChangeInfo {
+    owner: AccountInfo,
+}
+
+#[derive(Debug, Deserialize)]
+pub struct AccountInfo {
+    #[serde(rename = "_account_id")]
+    id: u64,
+}
+
+pub struct Chromium;
+
+impl Chromium {
+    async fn fetch_chromium_commit_author(
+        &self,
+        _repo: &str,
+        commit: &str,
+        client: &Arc<dyn HttpClient>,
+    ) -> Result<Option<AccountInfo>> {
+        let url = format!("{CHROMIUM_REVIEW_URL}/changes/{commit}");
+
+        let request = Request::get(&url)
+            .header("Content-Type", "application/json")
+            .follow_redirects(http_client::RedirectPolicy::FollowAll);
+
+        let mut response = client
+            .send(request.body(AsyncBody::default())?)
+            .await
+            .with_context(|| format!("error fetching Gerrit commit details at {:?}", url))?;
+
+        let mut body = Vec::new();
+        response.body_mut().read_to_end(&mut body).await?;
+
+        if response.status().is_client_error() {
+            let text = String::from_utf8_lossy(body.as_slice());
+            bail!(
+                "status error {}, response: {text:?}",
+                response.status().as_u16()
+            );
+        }
+
+        // Remove XSSI protection prefix.
+        let body_str = std::str::from_utf8(&body)?.trim_start_matches(")]}'");
+
+        serde_json::from_str::<ChangeInfo>(body_str)
+            .map(|change| Some(change.owner))
+            .context("failed to deserialize Gerrit change info")
+    }
+}
+
+#[async_trait]
+impl GitHostingProvider for Chromium {
+    fn name(&self) -> String {
+        "Chromium".to_string()
+    }
+
+    fn base_url(&self) -> Url {
+        Url::parse("https://chromium.googlesource.com").unwrap()
+    }
+
+    fn supports_avatars(&self) -> bool {
+        true
+    }
+
+    fn format_line_number(&self, line: u32) -> String {
+        format!("{line}")
+    }
+
+    fn format_line_numbers(&self, start_line: u32, _end_line: u32) -> String {
+        format!("{start_line}")
+    }
+
+    fn parse_remote_url(&self, url: &str) -> Option<ParsedGitRemote> {
+        let url = RemoteUrl::from_str(url).ok()?;
+
+        let host = url.host_str()?;
+        if host != self.base_url().host_str()? {
+            return None;
+        }
+
+        let path_segments = url.path_segments()?.collect::<Vec<_>>();
+        let joined_path = path_segments.join("/");
+        let repo = joined_path.trim_end_matches(".git");
+
+        Some(ParsedGitRemote {
+            owner: Arc::from(""),
+            repo: repo.into(),
+        })
+    }
+
+    fn build_commit_permalink(
+        &self,
+        remote: &ParsedGitRemote,
+        params: BuildCommitPermalinkParams,
+    ) -> Url {
+        let BuildCommitPermalinkParams { sha } = params;
+        let ParsedGitRemote { owner: _, repo } = remote;
+
+        self.base_url().join(&format!("{repo}/+/{sha}")).unwrap()
+    }
+
+    fn build_permalink(&self, remote: ParsedGitRemote, params: BuildPermalinkParams) -> Url {
+        let ParsedGitRemote { owner: _, repo } = remote;
+        let BuildPermalinkParams {
+            sha,
+            path,
+            selection,
+        } = params;
+
+        let mut permalink = self
+            .base_url()
+            .join(&format!("{repo}/+/{sha}/{path}"))
+            .unwrap();
+        permalink.set_fragment(
+            selection
+                .map(|selection| self.line_fragment(&selection))
+                .as_deref(),
+        );
+        permalink
+    }
+
+    fn extract_pull_request(&self, remote: &ParsedGitRemote, message: &str) -> Option<PullRequest> {
+        let capture = pull_request_regex().captures(message)?;
+        let url = Url::parse(capture.get(1)?.as_str()).unwrap();
+        let repo = capture.get(2)?.as_str();
+        if repo != remote.repo.as_ref() {
+            return None;
+        }
+
+        let number = capture.get(3)?.as_str().parse::<u32>().ok()?;
+
+        Some(PullRequest { number, url })
+    }
+
+    async fn commit_author_avatar_url(
+        &self,
+        _repo_owner: &str,
+        repo: &str,
+        commit: SharedString,
+        http_client: Arc<dyn HttpClient>,
+    ) -> Result<Option<Url>> {
+        let commit = commit.to_string();
+        let Some(author) = self
+            .fetch_chromium_commit_author(repo, &commit, &http_client)
+            .await?
+        else {
+            return Ok(None);
+        };
+
+        let mut avatar_url = Url::parse(&format!(
+            "{CHROMIUM_REVIEW_URL}/accounts/{}/avatar",
+            &author.id
+        ))?;
+        avatar_url.set_query(Some("size=128"));
+
+        Ok(Some(avatar_url))
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use indoc::indoc;
+    use pretty_assertions::assert_eq;
+
+    use super::*;
+
+    #[test]
+    fn test_parse_remote_url_given_https_url() {
+        let parsed_remote = Chromium
+            .parse_remote_url("https://chromium.googlesource.com/chromium/src")
+            .unwrap();
+
+        assert_eq!(
+            parsed_remote,
+            ParsedGitRemote {
+                owner: Arc::from(""),
+                repo: "chromium/src".into(),
+            }
+        );
+    }
+
+    #[test]
+    fn test_build_chromium_permalink() {
+        let permalink = Chromium.build_permalink(
+            ParsedGitRemote {
+                owner: Arc::from(""),
+                repo: "chromium/src".into(),
+            },
+            BuildPermalinkParams {
+                sha: "fea5080b182fc92e3be0c01c5dece602fe70b588",
+                path: "ui/base/cursor/cursor.h",
+                selection: None,
+            },
+        );
+
+        let expected_url = "https://chromium.googlesource.com/chromium/src/+/fea5080b182fc92e3be0c01c5dece602fe70b588/ui/base/cursor/cursor.h";
+        assert_eq!(permalink.to_string(), expected_url.to_string())
+    }
+
+    #[test]
+    fn test_build_chromium_permalink_with_single_line_selection() {
+        let permalink = Chromium.build_permalink(
+            ParsedGitRemote {
+                owner: Arc::from(""),
+                repo: "chromium/src".into(),
+            },
+            BuildPermalinkParams {
+                sha: "fea5080b182fc92e3be0c01c5dece602fe70b588",
+                path: "ui/base/cursor/cursor.h",
+                selection: Some(18..18),
+            },
+        );
+
+        let expected_url = "https://chromium.googlesource.com/chromium/src/+/fea5080b182fc92e3be0c01c5dece602fe70b588/ui/base/cursor/cursor.h#19";
+        assert_eq!(permalink.to_string(), expected_url.to_string())
+    }
+
+    #[test]
+    fn test_build_chromium_permalink_with_multi_line_selection() {
+        let permalink = Chromium.build_permalink(
+            ParsedGitRemote {
+                owner: Arc::from(""),
+                repo: "chromium/src".into(),
+            },
+            BuildPermalinkParams {
+                sha: "fea5080b182fc92e3be0c01c5dece602fe70b588",
+                path: "ui/base/cursor/cursor.h",
+                selection: Some(18..30),
+            },
+        );
+
+        let expected_url = "https://chromium.googlesource.com/chromium/src/+/fea5080b182fc92e3be0c01c5dece602fe70b588/ui/base/cursor/cursor.h#19";
+        assert_eq!(permalink.to_string(), expected_url.to_string())
+    }
+
+    #[test]
+    fn test_chromium_pull_requests() {
+        let remote = ParsedGitRemote {
+            owner: Arc::from(""),
+            repo: "chromium/src".into(),
+        };
+
+        let message = "This does not contain a pull request";
+        assert!(Chromium.extract_pull_request(&remote, message).is_none());
+
+        // Pull request number at end of "Reviewed-on:" line
+        let message = indoc! {r#"
+                Test commit header
+
+                Test commit description with multiple
+                lines.
+
+                Bug: 1193775, 1270302
+                Change-Id: Id15e9b4d75cce43ebd5fe34f0fb37d5e1e811b66
+                Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3310961
+                Reviewed-by: Test reviewer <test@example.com>
+                Cr-Commit-Position: refs/heads/main@{#1054973}
+                "#
+        };
+
+        assert_eq!(
+            Chromium
+                .extract_pull_request(&remote, &message)
+                .unwrap()
+                .url
+                .as_str(),
+            "https://chromium-review.googlesource.com/c/chromium/src/+/3310961"
+        );
+    }
+}