mailmap: add support for .mailmap files

CHANGELOG.md

@@ -46,6 +46,9 @@ to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
   address unconditionally. Only ASCII case folding is currently implemented,
   but this will likely change in the future.
 
+* Support for [`.mailmap`](https://git-scm.com/docs/gitmailmap) files has
+  been added.
+
 ### Fixed bugs
 
 ## [0.19.0] - 2024-07-03

Cargo.toml

@@ -55,6 +55,10 @@ gix = { version = "0.63.0", default-features = false, features = [
     "blob-diff",
 ] }
 gix-filter = "0.11.2"
+# We list `gix-{actor,mailmap}` separately, as they are used by
+# `jj_lib::mailmap` even when the Git backend is disabled.
+gix-actor = { version = "0.31.3" }
+gix-mailmap = { version = "0.23.4" }
 glob = "0.3.1"
 hex = "0.4.3"
 ignore = "0.4.20"

cli/src/cli_util.rs

@@ -41,6 +41,7 @@ use jj_lib::git_backend::GitBackend;
 use jj_lib::gitignore::{GitIgnoreError, GitIgnoreFile};
 use jj_lib::hex_util::to_reverse_hex;
 use jj_lib::id_prefix::IdPrefixContext;
+use jj_lib::mailmap::{read_current_mailmap, Mailmap};
 use jj_lib::matchers::Matcher;
 use jj_lib::merge::MergedTreeValue;
 use jj_lib::merged_tree::MergedTree;
@@ -73,6 +74,7 @@ use jj_lib::workspace::{
 };
 use jj_lib::{dag_walk, fileset, git, op_heads_store, op_walk, revset};
 use once_cell::unsync::OnceCell;
+use pollster::FutureExt;
 use tracing::instrument;
 use tracing_chrome::ChromeLayerBuilder;
 use tracing_subscriber::prelude::*;
@@ -712,6 +714,11 @@ impl WorkspaceCommandHelper {
         self.repo().view().get_wc_commit_id(self.workspace_id())
     }
 
+    pub fn current_mailmap(&self) -> Result<Mailmap, CommandError> {
+        // TODO: Consider figuring out a caching strategy for this.
+        Ok(read_current_mailmap(self.repo().as_ref(), self.workspace.workspace_id()).block_on()?)
+    }
+
     pub fn working_copy_shared_with_git(&self) -> bool {
         self.working_copy_shared_with_git
     }
@@ -996,6 +1003,8 @@ impl WorkspaceCommandHelper {
             self.settings.user_email(),
             &self.revset_extensions,
             Some(workspace_context),
+            // TODO: Consider handling errors here.
+            Rc::new(self.current_mailmap().unwrap_or_default()),
         )
     }
 

cli/src/commands/git/push.rs

@@ -289,14 +289,14 @@ pub fn cmd_git_push(
         if commit.description().is_empty() && !args.allow_empty_description {
             reasons.push("it has no description");
         }
-        if commit.author().name.is_empty()
-            || commit.author().name == UserSettings::USER_NAME_PLACEHOLDER
-            || commit.author().email.is_empty()
-            || commit.author().email == UserSettings::USER_EMAIL_PLACEHOLDER
-            || commit.committer().name.is_empty()
-            || commit.committer().name == UserSettings::USER_NAME_PLACEHOLDER
-            || commit.committer().email.is_empty()
-            || commit.committer().email == UserSettings::USER_EMAIL_PLACEHOLDER
+        if commit.author_raw().name.is_empty()
+            || commit.author_raw().name == UserSettings::USER_NAME_PLACEHOLDER
+            || commit.author_raw().email.is_empty()
+            || commit.author_raw().email == UserSettings::USER_EMAIL_PLACEHOLDER
+            || commit.committer_raw().name.is_empty()
+            || commit.committer_raw().name == UserSettings::USER_NAME_PLACEHOLDER
+            || commit.committer_raw().email.is_empty()
+            || commit.committer_raw().email == UserSettings::USER_EMAIL_PLACEHOLDER
         {
             reasons.push("it has no author and/or committer set");
         }

cli/src/commit_templater.rs

@@ -468,26 +468,43 @@ fn builtin_commit_methods<'repo>() -> CommitTemplateBuildMethodFnMap<'repo, Comm
             Ok(L::wrap_commit_list(out_property))
         },
     );
+    map.insert("author", |language, _build_ctx, self_property, function| {
+        function.expect_no_arguments()?;
+        let mailmap = language.revset_parse_context.mailmap().clone();
+        let out_property = self_property.map(move |commit| mailmap.author(&commit));
+        Ok(L::wrap_signature(out_property))
+    });
     map.insert(
-        "author",
+        "author_raw",
         |_language, _build_ctx, self_property, function| {
             function.expect_no_arguments()?;
-            let out_property = self_property.map(|commit| commit.author().clone());
+            let out_property = self_property.map(|commit| commit.author_raw().clone());
             Ok(L::wrap_signature(out_property))
         },
     );
     map.insert(
         "committer",
+        |language, _build_ctx, self_property, function| {
+            function.expect_no_arguments()?;
+            let mailmap = language.revset_parse_context.mailmap().clone();
+            let out_property = self_property.map(move |commit| mailmap.committer(&commit));
+            Ok(L::wrap_signature(out_property))
+        },
+    );
+    map.insert(
+        "committer_raw",
         |_language, _build_ctx, self_property, function| {
             function.expect_no_arguments()?;
-            let out_property = self_property.map(|commit| commit.committer().clone());
+            let out_property = self_property.map(|commit| commit.committer_raw().clone());
             Ok(L::wrap_signature(out_property))
         },
     );
     map.insert("mine", |language, _build_ctx, self_property, function| {
         function.expect_no_arguments()?;
+        let mailmap = language.revset_parse_context.mailmap().clone();
         let user_email = language.revset_parse_context.user_email().to_owned();
-        let out_property = self_property.map(move |commit| commit.author().email == user_email);
+        let out_property =
+            self_property.map(move |commit| mailmap.author(&commit).email == user_email);
         Ok(L::wrap_boolean(out_property))
     });
     map.insert(

cli/tests/runner.rs

@@ -45,6 +45,7 @@ mod test_immutable_commits;
 mod test_init_command;
 mod test_interdiff_command;
 mod test_log_command;
+mod test_mailmap;
 mod test_move_command;
 mod test_new_command;
 mod test_next_prev_commands;

cli/tests/test_mailmap.rs

@@ -0,0 +1,168 @@
+// Copyright 2024 The Jujutsu Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+use crate::common::{get_stdout_string, TestEnvironment};
+
+#[test]
+fn test_mailmap() {
+    let test_env = TestEnvironment::default();
+    test_env.jj_cmd_ok(test_env.env_root(), &["git", "init", "repo"]);
+    let repo_path = test_env.env_root().join("repo");
+
+    let mut mailmap = String::new();
+    let mailmap_path = repo_path.join(".mailmap");
+    let mut append_mailmap = move |extra| {
+        mailmap.push_str(extra);
+        std::fs::write(&mailmap_path, &mailmap).unwrap()
+    };
+
+    let run_as = |name: &str, email: &str, args: &[&str]| {
+        test_env
+            .jj_cmd(&repo_path, args)
+            .env("JJ_USER", name)
+            .env("JJ_EMAIL", email)
+            .assert()
+            .success()
+    };
+
+    append_mailmap("# test comment\n");
+
+    let stdout = test_env.jj_cmd_success(&repo_path, &["log", "-T", "author"]);
+    insta::assert_snapshot!(stdout, @r###"
+    @  Test User <[email protected]>
+    ◉
+    "###);
+
+    // Map an email address without any name change.
+    run_as("Test Üser", "[email protected]", &["new"]);
+    append_mailmap("<[email protected]> <[email protected]>\n");
+
+    let stdout = test_env.jj_cmd_success(&repo_path, &["log", "-T", "author"]);
+    insta::assert_snapshot!(stdout, @r###"
+    @  Test Üser <[email protected]>
+    ◉  Test User <[email protected]>
+    ◉
+    "###);
+
+    // Map an email address to a new name.
+    run_as("West User", "[email protected]", &["new"]);
+    append_mailmap("Fest User <[email protected]>\n");
+
+    let stdout = test_env.jj_cmd_success(&repo_path, &["log", "-T", "author"]);
+    insta::assert_snapshot!(stdout, @r###"
+    @  Fest User <[email protected]>
+    ◉  Test Üser <[email protected]>
+    ◉  Test User <[email protected]>
+    ◉
+    "###);
+
+    // Map an email address to a new name and email address.
+    run_as("Pest User", "[email protected]", &["new"]);
+    append_mailmap("Best User <[email protected]> <[email protected]>\n");
+
+    let stdout = test_env.jj_cmd_success(&repo_path, &["log", "-T", "author"]);
+    insta::assert_snapshot!(stdout, @r###"
+    @  Best User <[email protected]>
+    ◉  Fest User <[email protected]>
+    ◉  Test Üser <[email protected]>
+    ◉  Test User <[email protected]>
+    ◉
+    "###);
+
+    // Map an ambiguous email address using names for disambiguation.
+    run_as("Rest User", "user@test", &["new"]);
+    run_as("Vest User", "user@test", &["new"]);
+    append_mailmap(
+        &[
+            "Jest User <[email protected]> ReSt UsEr <UsEr@TeSt>\n",
+            "Zest User <[email protected]> vEsT uSeR <uSeR@tEsT>\n",
+        ]
+        .concat(),
+    );
+
+    let stdout = test_env.jj_cmd_success(&repo_path, &["log", "-T", "author"]);
+    insta::assert_snapshot!(stdout, @r###"
+    @  Zest User <[email protected]>
+    ◉  Jest User <[email protected]>
+    ◉  Best User <[email protected]>
+    ◉  Fest User <[email protected]>
+    ◉  Test Üser <[email protected]>
+    ◉  Test User <[email protected]>
+    ◉
+    "###);
+
+    // The `.mailmap` file in the current workspace’s @ commit should be used.
+    let stdout = test_env.jj_cmd_success(&repo_path, &["log", "-T", "author", "--at-operation=@-"]);
+    insta::assert_snapshot!(stdout, @r###"
+    @  Vest User <user@test>
+    ◉  Rest User <user@test>
+    ◉  Best User <[email protected]>
+    ◉  Fest User <[email protected]>
+    ◉  Test Üser <[email protected]>
+    ◉  Test User <[email protected]>
+    ◉
+    "###);
+
+    // The `author(pattern)` revset function should find mapped committers.
+    let stdout = test_env.jj_cmd_success(
+        &repo_path,
+        &["log", "-T", "author", "-r", "author(substring-i:bEsT)"],
+    );
+    insta::assert_snapshot!(stdout, @r###"
+    ◉  Best User <[email protected]>
+    │
+    ~
+    "###);
+
+    // The `author(pattern)` revset function should only search the mapped form.
+    // This matches Git’s behaviour and the principle of not surfacing raw
+    // signatures by default.
+    let stdout =
+        test_env.jj_cmd_success(&repo_path, &["log", "-T", "author", "-r", "author(pest)"]);
+    insta::assert_snapshot!(stdout, @r###"
+    "###);
+
+    // The `author_raw(pattern)` revset function should search the unmapped
+    // commit data.
+    let stdout = test_env.jj_cmd_success(
+        &repo_path,
+        &["log", "-T", "author", "-r", "author_raw(\"user@test\")"],
+    );
+    insta::assert_snapshot!(stdout, @r###"
+    @  Zest User <[email protected]>
+    ◉  Jest User <[email protected]>
+    │
+    ~
+    "###);
+
+    // `mine()` should find commits that map to the current `user.email`.
+    let assert = run_as(
+        "Tëst Üser",
+        "[email protected]",
+        &["log", "-T", "author", "-r", "mine()"],
+    );
+    insta::assert_snapshot!(get_stdout_string(&assert), @r###"
+    ◉  Test Üser <[email protected]>
+    ◉  Test User <[email protected]>
+    │
+    ~
+    "###);
+
+    // `mine()` should only search the mapped author; this may be confusing in this
+    // case, but matches the semantics of it expanding to `author(‹user.email›)`.
+    let stdout: String =
+        test_env.jj_cmd_success(&repo_path, &["log", "-T", "author", "-r", "mine()"]);
+    insta::assert_snapshot!(stdout, @r###"
+    "###);
+}

cli/tests/test_revset_output.rs

@@ -290,7 +290,7 @@ fn test_function_name_hint() {
       | ^-----^
       |
       = Function "author_" doesn't exist
-    Hint: Did you mean "author", "my_author"?
+    Hint: Did you mean "author", "author_raw", "my_author"?
     "###);
 
     insta::assert_snapshot!(evaluate_err("my_branches"), @r###"

docs/revsets.md

@@ -251,12 +251,18 @@ revsets (expressions) as arguments.
 * `author(pattern)`: Commits with the author's name or email matching the given
   [string pattern](#string-patterns).
 
+* `author_raw(pattern)`: Like `author(pattern)`, but ignoring any mappings in
+  the [`.mailmap` file](https://git-scm.com/docs/gitmailmap).
+
 * `mine()`: Commits where the author's email matches the email of the current
   user.
 
 * `committer(pattern)`: Commits with the committer's  name or email matching the
 given [string pattern](#string-patterns).
 
+* `committer_raw(pattern)`: Like `committer(pattern)`, but ignoring any
+  mappings in the [`.mailmap` file](https://git-scm.com/docs/gitmailmap).
+
 * `empty()`: Commits modifying no files. This also includes `merges()` without
   user modifications and `root()`.
 

docs/templates.md

@@ -73,7 +73,11 @@ This type cannot be printed. The following methods are defined.
 * `commit_id() -> CommitId`
 * `parents() -> List<Commit>`
 * `author() -> Signature`
+* `author_raw() -> Signature`: Like `author()`, but ignoring any mappings in
+  the [`.mailmap` file](https://git-scm.com/docs/gitmailmap).
 * `committer() -> Signature`
+* `committer_raw() -> Signature`: Like `committer()`, but ignoring any mappings
+  in the [`.mailmap` file](https://git-scm.com/docs/gitmailmap).
 * `mine() -> Boolean`: Commits where the author's email matches the email of the current
   user.
 * `working_copies() -> String`: For multi-workspace repository, indicate

lib/Cargo.toml

@@ -45,6 +45,8 @@ futures = { workspace = true }
 git2 = { workspace = true, optional = true }
 gix = { workspace = true, optional = true }
 gix-filter = { workspace = true, optional = true }
+gix-actor = { workspace = true }
+gix-mailmap = { workspace = true }
 glob = { workspace = true }
 hex = { workspace = true }
 ignore = { workspace = true }