// Copyright 2022 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 std::path::PathBuf;

use indoc::indoc;
use testutils::TestResult;

use crate::common::CommandOutput;
use crate::common::TestEnvironment;
use crate::common::TestWorkDir;
use crate::common::force_interactive;

#[test]
fn test_describe() -> TestResult {
    let mut test_env = TestEnvironment::default();
    let edit_script = test_env.set_up_fake_editor();
    test_env.run_jj_in(".", ["git", "init", "repo"]).success();
    let work_dir = test_env.work_dir("repo");

    // Set a description using `-m` flag
    let output = work_dir.run_jj(["describe", "-m", "description from CLI"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Working copy  (@) now at: qpvuntsm 7b186b4f (empty) description from CLI
    Parent commit (@-)      : zzzzzzzz 00000000 (empty) (no description set)
    [EOF]
    ");

    // Set the same description using `-m` flag, but with explicit newline
    let output = work_dir.run_jj(["describe", "-m", "description from CLI\n"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Nothing changed.
    [EOF]
    ");

    // Check that the text file gets initialized with the current description and
    // make no changes
    std::fs::write(&edit_script, "dump editor0")?;
    let output = work_dir.run_jj(["describe"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Nothing changed.
    [EOF]
    ");
    insta::assert_snapshot!(
        std::fs::read_to_string(test_env.env_root().join("editor0"))?, @r#"
    description from CLI

    JJ: Change ID: qpvuntsm
    JJ:
    JJ: Lines starting with "JJ:" (like this one) will be removed.
    "#);

    // Set a description in editor
    std::fs::write(&edit_script, "write\ndescription from editor")?;
    let output = work_dir.run_jj(["describe"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Working copy  (@) now at: qpvuntsm 28173c3e (empty) description from editor
    Parent commit (@-)      : zzzzzzzz 00000000 (empty) (no description set)
    [EOF]
    ");

    // Lines in editor starting with "JJ: " are ignored
    std::fs::write(
        &edit_script,
        "write\nJJ: ignored\ndescription among comment\nJJ: ignored",
    )?;
    let output = work_dir.run_jj(["describe"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Working copy  (@) now at: qpvuntsm e7488502 (empty) description among comment
    Parent commit (@-)      : zzzzzzzz 00000000 (empty) (no description set)
    [EOF]
    ");

    // Multi-line description
    std::fs::write(&edit_script, "write\nline1\nline2\n\nline4\n\n")?;
    let output = work_dir.run_jj(["describe"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Working copy  (@) now at: qpvuntsm 7438c202 (empty) line1
    Parent commit (@-)      : zzzzzzzz 00000000 (empty) (no description set)
    [EOF]
    ");
    let output = work_dir.run_jj(["log", "--no-graph", "-r@", "-Tdescription"]);
    insta::assert_snapshot!(output, @"
    line1
    line2

    line4
    [EOF]
    ");

    // Multi-line description again with CRLF, which should make no changes
    std::fs::write(&edit_script, "write\nline1\r\nline2\r\n\r\nline4\r\n\r\n")?;
    let output = work_dir.run_jj(["describe"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Nothing changed.
    [EOF]
    ");

    // Multi-line description starting with newlines
    std::fs::write(&edit_script, "write\n\n\nline1\nline2")?;
    let output = work_dir.run_jj(["describe"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Working copy  (@) now at: qpvuntsm f38e2bd7 (empty) line1
    Parent commit (@-)      : zzzzzzzz 00000000 (empty) (no description set)
    [EOF]
    ");
    let output = work_dir.run_jj(["log", "--no-graph", "-r@", "-Tdescription"]);
    insta::assert_snapshot!(output, @"
    line1
    line2
    [EOF]
    ");

    // Clear description
    let output = work_dir.run_jj(["describe", "-m", ""]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Working copy  (@) now at: qpvuntsm 7c00df81 (empty) (no description set)
    Parent commit (@-)      : zzzzzzzz 00000000 (empty) (no description set)
    [EOF]
    ");
    std::fs::write(&edit_script, "write\n")?;
    let output = work_dir.run_jj(["describe"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Nothing changed.
    [EOF]
    ");

    // Fails if the editor fails
    std::fs::write(&edit_script, "fail")?;
    let output = work_dir.run_jj(["describe"]);
    insta::with_settings!({
        filters => [
            (r"\bEditor '[^']*'", "Editor '<redacted>'"),
            (r"in .*(editor-)[^.]*(\.jjdescription)\b", "in <redacted>$1<redacted>$2"),
            ("exit code", "exit status"), // Windows
        ],
    }, {
        insta::assert_snapshot!(output, @"
        ------- stderr -------
        Error: Failed to edit description
        Caused by: Editor '<redacted>' exited with exit status: 1
        Hint: Edited description is left in <redacted>editor-<redacted>.jjdescription
        [EOF]
        [exit status: 1]
        ");
    });

    // ignore everything after the first ignore-rest line
    std::fs::write(
        &edit_script,
        indoc! {"
            write
            description from editor

            content of message from editor
            JJ: ignore-rest
            content after ignore line should not be included
            JJ: ignore-rest
            ignore everything until EOF or next description
        "},
    )?;
    let output = work_dir.run_jj(["describe"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Working copy  (@) now at: qpvuntsm 0ec68094 (empty) description from editor
    Parent commit (@-)      : zzzzzzzz 00000000 (empty) (no description set)
    [EOF]
    ");
    let output = work_dir.run_jj(["log", "--no-graph", "-r@", "-Tdescription"]);
    insta::assert_snapshot!(output, @"
    description from editor

    content of message from editor
    [EOF]
    ");
    Ok(())
}

#[test]
fn test_describe_editor_env() {
    let test_env = TestEnvironment::default();
    test_env.run_jj_in(".", ["git", "init", "repo"]).success();
    let work_dir = test_env.work_dir("repo");

    // Fails if the editor doesn't exist
    let output = work_dir.run_jj_with(|cmd| {
        cmd.arg("describe")
            .env("EDITOR", "this-editor-does-not-exist")
    });
    insta::assert_snapshot!(
        output.normalize_stderr_with(|s| s.split_inclusive('\n').take(3).collect()), @"
    ------- stderr -------
    Error: Failed to edit description
    Caused by:
    1: Failed to run editor 'this-editor-does-not-exist'
    [EOF]
    [exit status: 1]
    ");

    // `$VISUAL` overrides `$EDITOR`
    let output = work_dir.run_jj_with(|cmd| {
        cmd.arg("describe")
            .env("VISUAL", "bad-editor-from-visual-env")
            .env("EDITOR", "bad-editor-from-editor-env")
    });
    insta::assert_snapshot!(
        output.normalize_stderr_with(|s| s.split_inclusive('\n').take(3).collect()), @"
    ------- stderr -------
    Error: Failed to edit description
    Caused by:
    1: Failed to run editor 'bad-editor-from-visual-env'
    [EOF]
    [exit status: 1]
    ");

    // `ui.editor` config overrides `$VISUAL`
    test_env.add_config(r#"ui.editor = "bad-editor-from-config""#);
    let output = work_dir.run_jj_with(|cmd| {
        cmd.arg("describe")
            .env("VISUAL", "bad-editor-from-visual-env")
    });
    insta::assert_snapshot!(
        output.normalize_stderr_with(|s| s.split_inclusive('\n').take(3).collect()), @"
    ------- stderr -------
    Error: Failed to edit description
    Caused by:
    1: Failed to run editor 'bad-editor-from-config'
    [EOF]
    [exit status: 1]
    ");

    // `$JJ_EDITOR` overrides `ui.editor` config
    let output = work_dir.run_jj_with(|cmd| {
        cmd.arg("describe")
            .env("JJ_EDITOR", "bad-jj-editor-from-jj-editor-env")
    });
    insta::assert_snapshot!(
        output.normalize_stderr_with(|s| s.split_inclusive('\n').take(3).collect()), @"
    ------- stderr -------
    Error: Failed to edit description
    Caused by:
    1: Failed to run editor 'bad-jj-editor-from-jj-editor-env'
    [EOF]
    [exit status: 1]
    ");
}

#[test]
fn test_describe_no_matching_revisions() {
    let test_env = TestEnvironment::default();
    test_env.run_jj_in(".", ["git", "init", "repo"]).success();
    let work_dir = test_env.work_dir("repo");
    let output = work_dir.run_jj(["describe", "none()"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    No revisions to describe.
    [EOF]
    ");
}

#[test]
fn test_describe_multiple_commits() -> TestResult {
    let mut test_env = TestEnvironment::default();
    let edit_script = test_env.set_up_fake_editor();
    test_env.run_jj_in(".", ["git", "init", "repo"]).success();
    let work_dir = test_env.work_dir("repo");

    // Initial setup
    work_dir.run_jj(["new"]).success();
    work_dir.run_jj(["new"]).success();
    insta::assert_snapshot!(get_log_output(&work_dir), @"
    @  3cd3b246e098
    ○  43444d88b009
    ○  e8849ae12c70
    ◆  000000000000
    [EOF]
    ");

    // Set the description of multiple commits using `-m` flag
    let output = work_dir.run_jj(["describe", "-r@", "-r@--", "-m", "description from CLI"]);
    insta::assert_snapshot!(output, @r"
    ------- stderr -------
    Updated 2 commits.
    Rebased 1 descendant commits.
    Working copy  (@) now at: kkmpptxz 4c3ccb9d (empty) description from CLI
    Parent commit (@-)      : rlvkpnrz 650ac8f2 (empty) (no description set)
    [EOF]
    ");
    insta::assert_snapshot!(get_log_output(&work_dir), @"
    @  4c3ccb9d4fb2 description from CLI
    ○  650ac8f249be
    ○  0ff65c91377a description from CLI
    ◆  000000000000
    [EOF]
    ");

    // Check that the text file gets initialized with the current description of
    // each commit and doesn't update commits if no changes are made.
    // Commit descriptions are edited in topological order
    std::fs::write(&edit_script, "dump editor0")?;
    let output = work_dir.run_jj(["describe", "-r@", "@-"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Nothing changed.
    [EOF]
    ");
    insta::assert_snapshot!(
        std::fs::read_to_string(test_env.env_root().join("editor0"))?, @r#"
    JJ: Enter or edit commit descriptions after the `JJ: describe` lines.
    JJ: Warning:
    JJ: - The text you enter will be lost on a syntax error.
    JJ: - The syntax of the separator lines may change in the future.
    JJ:
    JJ: describe 650ac8f249be -------


    JJ: Change ID: rlvkpnrz
    JJ:
    JJ: describe 4c3ccb9d4fb2 -------
    description from CLI

    JJ: Change ID: kkmpptxz
    JJ:
    JJ: Lines starting with "JJ:" (like this one) will be removed.
    "#);

    // Set the description of multiple commits in the editor
    std::fs::write(
        &edit_script,
        indoc! {"
            write
            JJ: Enter or edit commit descriptions after the `JJ: describe` lines.

            JJ: More header tests. Library tests verify parsing in other situations.

            JJ: describe 650ac8f249be -------
            description from editor of @-

            further commit message of @-

            JJ: describe 4c3ccb9d4fb2 -------
            description from editor of @

            further commit message of @

            JJ: Lines starting with \"JJ: \" (like this one) will be removed.
        "},
    )?;
    let output = work_dir.run_jj(["describe", "@", "@-"]);
    insta::assert_snapshot!(output, @r"
    ------- stderr -------
    Updated 2 commits.
    Working copy  (@) now at: kkmpptxz 87c0f3c7 (empty) description from editor of @
    Parent commit (@-)      : rlvkpnrz 9b9041eb (empty) description from editor of @-
    [EOF]
    ");
    insta::assert_snapshot!(get_log_output(&work_dir), @"
    @  87c0f3c75a22 description from editor of @
    │
    │  further commit message of @
    ○  9b9041eb2f04 description from editor of @-
    │
    │  further commit message of @-
    ○  0ff65c91377a description from CLI
    ◆  000000000000
    [EOF]
    ");

    // Fails if the edited message has a commit with multiple descriptions
    std::fs::write(
        &edit_script,
        indoc! {"
            write
            JJ: describe 9b9041eb2f04 -------
            first description from editor of @-

            further commit message of @-

            JJ: describe 9b9041eb2f04 -------
            second description from editor of @-

            further commit message of @-

            JJ: describe 87c0f3c75a22 -------
            updated description from editor of @

            further commit message of @

            JJ: Lines starting with \"JJ: \" (like this one) will be removed.
        "},
    )?;
    let output = work_dir.run_jj(["describe", "@", "@-"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Error: The following commits were found in the edited message multiple times: 9b9041eb2f04
    [EOF]
    [exit status: 1]
    ");

    // Fails if the edited message has unexpected commit IDs
    std::fs::write(
        &edit_script,
        indoc! {"
            write
            JJ: describe 000000000000 -------
            unexpected commit ID

            JJ: describe 9b9041eb2f04 -------
            description from editor of @-

            further commit message of @-

            JJ: describe 87c0f3c75a22 -------
            description from editor of @

            further commit message of @

            JJ: Lines starting with \"JJ: \" (like this one) will be removed.
        "},
    )?;
    let output = work_dir.run_jj(["describe", "@", "@-"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Error: The following commits were not being edited, but were found in the edited message: 000000000000
    [EOF]
    [exit status: 1]
    ");

    // Fails if the edited message has missing commit messages
    std::fs::write(
        &edit_script,
        indoc! {"
            write
            JJ: describe 87c0f3c75a22 -------
            description from editor of @

            further commit message of @

            JJ: Lines starting with \"JJ: \" (like this one) will be removed.
        "},
    )?;
    let output = work_dir.run_jj(["describe", "@", "@-"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Error: The description for the following commits were not found in the edited message: 9b9041eb2f04
    [EOF]
    [exit status: 1]
    ");

    // Fails if the edited message has a line which does not have any preceding
    // `JJ: describe` headers
    std::fs::write(
        &edit_script,
        indoc! {"
            write
            description from editor of @-

            JJ: describe 9b9041eb2f04 -------
            description from editor of @

            JJ: Lines starting with \"JJ: \" (like this one) will be removed.
        "},
    )?;
    let output = work_dir.run_jj(["describe", "@", "@-"]);
    insta::assert_snapshot!(output, @r#"
    ------- stderr -------
    Error: Found the following line without a commit header: "description from editor of @-"
    [EOF]
    [exit status: 1]
    "#);

    // Fails if the editor fails
    std::fs::write(&edit_script, "fail")?;
    let output = work_dir.run_jj(["describe", "@", "@-"]);
    insta::with_settings!({
        filters => [
            (r"\bEditor '[^']*'", "Editor '<redacted>'"),
            (r"in .*(editor-)[^.]*(\.jjdescription)\b", "in <redacted>$1<redacted>$2"),
            ("exit code", "exit status"), // Windows
        ],
    }, {
        insta::assert_snapshot!(output, @"
        ------- stderr -------
        Error: Failed to edit description
        Caused by: Editor '<redacted>' exited with exit status: 1
        Hint: Edited description is left in <redacted>editor-<redacted>.jjdescription
        [EOF]
        [exit status: 1]
        ");
    });

    // describe lines should take priority over ignore-rest
    std::fs::write(
        &edit_script,
        indoc! {"
            write
            JJ: describe 9b9041eb2f04 -------
            description from editor for @-

            JJ: ignore-rest
            content after ignore-rest should not be included

            JJ: describe 0ff65c91377a -------
            description from editor for @--

            JJ: ignore-rest
            each commit should skip their own ignore-rest
        "},
    )?;
    let output = work_dir.run_jj(["describe", "@-", "@--"]);
    insta::assert_snapshot!(output, @r"
    ------- stderr -------
    Updated 2 commits.
    Rebased 1 descendant commits.
    Working copy  (@) now at: kkmpptxz 5a6249e9 (empty) description from editor of @
    Parent commit (@-)      : rlvkpnrz d1c1edbd (empty) description from editor for @-
    [EOF]
    ");
    insta::assert_snapshot!(get_log_output(&work_dir), @"
    @  5a6249e9e71a description from editor of @
    │
    │  further commit message of @
    ○  d1c1edbd5595 description from editor for @-
    ○  a8bf976d72fb description from editor for @--
    ◆  000000000000
    [EOF]
    ");
    Ok(())
}

#[test]
fn test_describe_with_draft_template() {
    let mut test_env = TestEnvironment::default();
    let edit_script = test_env.set_up_fake_editor();
    test_env.run_jj_in(".", ["git", "init", "repo"]).success();
    let work_dir = test_env.work_dir("repo");

    // Initial setup
    work_dir.write_file("a.txt", "aaaa\nbbbb\ncccc\n");
    work_dir.run_jj(["commit", "-m=first"]).success();
    work_dir.write_file("a.txt", b"aaaa\ncccc\ndddd\n\xff\n");
    work_dir.run_jj(["describe", "-m=second"]).success();
    insta::assert_snapshot!(get_log_output(&work_dir), @"
    @  c43cce883e27 second
    ○  8620a92b036c first
    ◆  000000000000
    [EOF]
    ");

    // Dump the default commit description template
    std::fs::write(&edit_script, "dump editor0").unwrap();
    let output = work_dir.run_jj(["describe"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Nothing changed.
    [EOF]
    ");
    insta::assert_snapshot!(
        std::fs::read_to_string(test_env.env_root().join("editor0")).unwrap(), @r#"
    second

    JJ: Change ID: rlvkpnrz
    JJ: This commit contains the following changes:
    JJ:     M a.txt
    JJ:
    JJ: Lines starting with "JJ:" (like this one) will be removed.
    "#);

    // Builtin template with diff content
    std::fs::write(&edit_script, "dump editor0").unwrap();
    let output = work_dir.run_jj([
        "describe",
        "--config=templates.draft_commit_description='builtin_draft_commit_description_with_diff'",
    ]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Nothing changed.
    [EOF]
    ");
    insta::assert_snapshot!(
        std::fs::read_to_string(test_env.env_root().join("editor0")).unwrap(), @r#"
    second

    JJ: Change ID: rlvkpnrz
    JJ: This commit contains the following changes:
    JJ:     M a.txt

    JJ: ignore-rest
    diff --git a/a.txt b/a.txt
    index edd13ee535..12e5763da1 100644
    --- a/a.txt
    +++ b/a.txt
    @@ -1,3 +1,4 @@
     aaaa
    -bbbb
     cccc
    +dddd
    +�

    JJ: Lines starting with "JJ:" (like this one) will be removed.
    "#);

    // Newline auto-inserted when template produces content without newline
    std::fs::write(&edit_script, "dump editor0").unwrap();
    let output = work_dir.run_jj([
        "describe",
        "--config=templates.draft_commit_description='change_id'",
    ]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Working copy  (@) now at: rlvkpnrz 1fd03b68 rlvkpnrzqnoowoytxnquwvuryrwnrmlp
    Parent commit (@-)      : qpvuntsm 8620a92b first
    [EOF]
    ");
    insta::assert_snapshot!(
        std::fs::read_to_string(test_env.env_root().join("editor0")).unwrap(), @r#"
    rlvkpnrzqnoowoytxnquwvuryrwnrmlp

    JJ: Lines starting with "JJ:" (like this one) will be removed.
    "#);

    // Newline auto-inserted when template produces empty string
    std::fs::write(&edit_script, "dump editor0").unwrap();
    let output = work_dir.run_jj([
        "describe",
        r#"--config=templates.draft_commit_description='""'"#,
    ]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Working copy  (@) now at: rlvkpnrz b59daf76 (no description set)
    Parent commit (@-)      : qpvuntsm 8620a92b first
    [EOF]
    ");
    let editor0 = std::fs::read_to_string(test_env.env_root().join("editor0")).unwrap();
    insta::assert_snapshot!(format!("-----\n{editor0}-----\n"), @r#"
    -----

    JJ: Lines starting with "JJ:" (like this one) will be removed.
    -----
    "#);
}

#[test]
fn test_multiple_message_args() {
    let test_env = TestEnvironment::default();
    test_env.run_jj_in(".", ["git", "init", "repo"]).success();
    let work_dir = test_env.work_dir("repo");

    // Set a description using `-m` flag
    let output = work_dir.run_jj([
        "describe",
        "-m",
        "First Paragraph from CLI",
        "-m",
        "Second Paragraph from CLI",
    ]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Working copy  (@) now at: qpvuntsm 9b8ad205 (empty) First Paragraph from CLI
    Parent commit (@-)      : zzzzzzzz 00000000 (empty) (no description set)
    [EOF]
    ");

    let output = work_dir.run_jj(["log", "--no-graph", "-r@", "-Tdescription"]);
    insta::assert_snapshot!(output, @"
    First Paragraph from CLI

    Second Paragraph from CLI
    [EOF]
    ");

    // Set the same description, with existing newlines
    let output = work_dir.run_jj([
        "describe",
        "-m",
        "First Paragraph from CLI\n",
        "-m",
        "Second Paragraph from CLI\n",
    ]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Nothing changed.
    [EOF]
    ");

    // Use an empty -m flag between paragraphs to insert an extra blank line
    let output = work_dir.run_jj([
        "describe",
        "-m",
        "First Paragraph from CLI\n",
        "--message",
        "",
        "-m",
        "Second Paragraph from CLI",
    ]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Working copy  (@) now at: qpvuntsm ac46ea93 (empty) First Paragraph from CLI
    Parent commit (@-)      : zzzzzzzz 00000000 (empty) (no description set)
    [EOF]
    ");

    let output = work_dir.run_jj(["log", "--no-graph", "-r@", "-Tdescription"]);
    insta::assert_snapshot!(output, @"
    First Paragraph from CLI


    Second Paragraph from CLI
    [EOF]
    ");
}

#[test]
fn test_describe_description_file_removed() {
    let mut test_env = TestEnvironment::default();
    let edit_script = test_env.set_up_fake_editor();
    test_env.run_jj_in(".", ["git", "init", "repo"]).success();
    let work_dir = test_env.work_dir("repo");

    // Description file misplaced by the user or a faulty editor
    std::fs::write(edit_script, "delete").unwrap();
    let output = work_dir.run_jj(["describe"]);
    insta::with_settings!({
        filters => [
            (r"(access|in) .*(editor-)[^.]*(\.jjdescription)\b", "$1 <redacted>$2<redacted>$3"),
            ("The system cannot find the file specified.", "No such file or directory"),
        ],
    }, {
        insta::assert_snapshot!(output, @"
        ------- stderr -------
        Error: Failed to edit description
        Caused by:
        1: Cannot access <redacted>editor-<redacted>.jjdescription
        2: No such file or directory (os error 2)
        Hint: Edited description is left in <redacted>editor-<redacted>.jjdescription
        [EOF]
        [exit status: 1]
        ");
    });
}

#[test]
fn test_describe_stdin_description() {
    let test_env = TestEnvironment::default();
    test_env.run_jj_in(".", ["git", "init", "repo"]).success();
    let work_dir = test_env.work_dir("repo");
    let output = work_dir.run_jj_with(|cmd| {
        force_interactive(cmd)
            .args(["describe", "--stdin"])
            .write_stdin("first stdin\nsecond stdin")
    });
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Working copy  (@) now at: qpvuntsm b9990801 (empty) first stdin
    Parent commit (@-)      : zzzzzzzz 00000000 (empty) (no description set)
    [EOF]
    ");
    let output = work_dir.run_jj(["log", "--no-graph", "-r@", "-Tdescription"]);
    insta::assert_snapshot!(output, @"
    first stdin
    second stdin
    [EOF]
    ");
}

#[test]
fn test_describe_default_description() -> TestResult {
    let mut test_env = TestEnvironment::default();
    let edit_script = test_env.set_up_fake_editor();
    test_env.run_jj_in(".", ["git", "init", "repo"]).success();
    test_env.add_config(r#"template-aliases.default_commit_description = '"\n\nTESTED=TODO\n"'"#);
    let work_dir = test_env.work_dir("repo");

    work_dir.write_file("file1", "foo\n");
    work_dir.write_file("file2", "bar\n");
    std::fs::write(edit_script, ["dump editor"].join("\0"))?;
    let output = work_dir.run_jj(["describe"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Working copy  (@) now at: qpvuntsm 7276dfff TESTED=TODO
    Parent commit (@-)      : zzzzzzzz 00000000 (empty) (no description set)
    [EOF]
    ");
    insta::assert_snapshot!(
        std::fs::read_to_string(test_env.env_root().join("editor"))?, @r#"


    TESTED=TODO

    JJ: Change ID: qpvuntsm
    JJ: This commit contains the following changes:
    JJ:     A file1
    JJ:     A file2
    JJ:
    JJ: Lines starting with "JJ:" (like this one) will be removed.
    "#);

    Ok(())
}

#[test]
fn test_describe_avoids_unc() -> TestResult {
    let mut test_env = TestEnvironment::default();
    let edit_script = test_env.set_up_fake_editor();
    test_env.run_jj_in(".", ["git", "init", "repo"]).success();
    let work_dir = test_env.work_dir("repo");

    std::fs::write(edit_script, "dump-path path")?;
    work_dir.run_jj(["describe"]).success();

    let edited_path = PathBuf::from(std::fs::read_to_string(test_env.env_root().join("path"))?);
    // While `assert!(!edited_path.starts_with("//?/"))` could work here in most
    // cases, it fails when it is not safe to strip the prefix, such as paths
    // over 260 chars.
    assert_eq!(edited_path, dunce::simplified(&edited_path));
    Ok(())
}

#[test]
fn test_describe_with_editor_and_message_args_opens_editor() -> TestResult {
    let mut test_env = TestEnvironment::default();
    let edit_script = test_env.set_up_fake_editor();
    test_env.run_jj_in(".", ["git", "init", "repo"]).success();
    let work_dir = test_env.work_dir("repo");

    std::fs::write(edit_script, ["dump editor"].join("\0"))?;
    let output = work_dir.run_jj(["describe", "-m", "message from command line", "--editor"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Working copy  (@) now at: qpvuntsm f9bee6de (empty) message from command line
    Parent commit (@-)      : zzzzzzzz 00000000 (empty) (no description set)
    [EOF]
    ");
    insta::assert_snapshot!(
        std::fs::read_to_string(test_env.env_root().join("editor"))?, @r#"
    message from command line

    JJ: Change ID: qpvuntsm
    JJ:
    JJ: Lines starting with "JJ:" (like this one) will be removed.
    "#);
    Ok(())
}

#[test]
fn test_describe_change_with_existing_message_with_editor_and_message_args_opens_editor()
-> TestResult {
    let mut test_env = TestEnvironment::default();
    let edit_script = test_env.set_up_fake_editor();
    test_env.run_jj_in(".", ["git", "init", "repo"]).success();
    let work_dir = test_env.work_dir("repo");

    work_dir
        .run_jj(["describe", "-m", "original message"])
        .success();

    std::fs::write(edit_script, ["dump editor"].join("\0"))?;
    let output = work_dir.run_jj(["describe", "-m", "new message", "--editor"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Working copy  (@) now at: qpvuntsm f8f14f7c (empty) new message
    Parent commit (@-)      : zzzzzzzz 00000000 (empty) (no description set)
    [EOF]
    ");
    insta::assert_snapshot!(
        std::fs::read_to_string(test_env.env_root().join("editor"))?, @r#"
    new message

    JJ: Change ID: qpvuntsm
    JJ:
    JJ: Lines starting with "JJ:" (like this one) will be removed.
    "#);
    Ok(())
}

#[test]
fn test_add_trailer() {
    let mut test_env = TestEnvironment::default();
    test_env.run_jj_in(".", ["git", "init", "repo"]).success();
    let _edit_script = test_env.set_up_fake_editor();
    let work_dir = test_env.work_dir("repo");

    // Set a description using `-m` flag
    let output = work_dir.run_jj([
        "describe",
        "-m",
        "Message from CLI",
        "--config",
        r#"templates.commit_trailers='"Signed-off-by: " ++ committer'"#,
    ]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Working copy  (@) now at: qpvuntsm 55c6f83d (empty) Message from CLI
    Parent commit (@-)      : zzzzzzzz 00000000 (empty) (no description set)
    [EOF]
    ");

    let output = work_dir.run_jj(["log", "--no-graph", "-r@", "-Tdescription"]);
    insta::assert_snapshot!(output, @"
    Message from CLI

    Signed-off-by: Test User <test.user@example.com>
    [EOF]
    ");

    // multiple trailers may be used
    let output = work_dir.run_jj([
        "describe",
        "--config",
        r#"templates.commit_trailers='"CC: alice@example.com\nChange-Id: I6a6a6964" ++ self.change_id().normal_hex()'"#,
    ]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Working copy  (@) now at: qpvuntsm 2b2e302d (empty) Message from CLI
    Parent commit (@-)      : zzzzzzzz 00000000 (empty) (no description set)
    [EOF]
    ");

    let output = work_dir.run_jj(["log", "--no-graph", "-r@", "-Tdescription"]);
    insta::assert_snapshot!(output, @"
    Message from CLI

    Signed-off-by: Test User <test.user@example.com>
    CC: alice@example.com
    Change-Id: I6a6a69649a45c67d3e96a7e5007c110ede34dec5
    [EOF]
    ");

    // it won't create a duplicate entry
    let output = work_dir.run_jj([
        "describe",
        "--config",
        r#"templates.commit_trailers='"CC: alice@example.com"'"#,
    ]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Nothing changed.
    [EOF]
    ");

    let output = work_dir.run_jj(["log", "--no-graph", "-r@", "-Tdescription"]);
    insta::assert_snapshot!(output, @"
    Message from CLI

    Signed-off-by: Test User <test.user@example.com>
    CC: alice@example.com
    Change-Id: I6a6a69649a45c67d3e96a7e5007c110ede34dec5
    [EOF]
    ");

    // invalid generated trailers generate an error
    let output = work_dir.run_jj([
        "describe",
        "--config",
        r#"templates.commit_trailers='"this is an invalid trailer"'"#,
    ]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Error: Invalid trailer line: this is an invalid trailer
    [EOF]
    [exit status: 1]
    ");

    // it doesn't modify a commit with an empty description
    let output = work_dir.run_jj(["new"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Working copy  (@) now at: yostqsxw dbea21e1 (empty) (no description set)
    Parent commit (@-)      : qpvuntsm 2b2e302d (empty) Message from CLI
    [EOF]
    ");
    let output = work_dir.run_jj([
        "describe",
        "--message=",
        "--config",
        r#"templates.commit_trailers='"CC: alice@example.com"'"#,
    ]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Nothing changed.
    [EOF]
    ");

    // Invalid trailer content
    work_dir.write_file("data.txt", b"\xff\n");
    let output = work_dir.run_jj([
        "describe",
        "-m=content",
        "--config",
        r#"templates.commit_trailers='indent("Content: ", diff.git())'"#,
    ]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Error: Trailers should be valid utf-8
    [EOF]
    [exit status: 1]
    ");
}

#[test]
fn test_add_trailer_committer() -> TestResult {
    let mut test_env = TestEnvironment::default();
    test_env.run_jj_in(".", ["git", "init", "repo"]).success();
    let edit_script = test_env.set_up_fake_editor();
    let work_dir = test_env.work_dir("repo");
    test_env.add_config(
        r#"[templates]
        commit_trailers = '''"Signed-off-by: " ++ committer.email()'''"#,
    );

    let output = work_dir.run_jj(["describe", "-m", "Message from CLI"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Working copy  (@) now at: qpvuntsm 67458426 (empty) Message from CLI
    Parent commit (@-)      : zzzzzzzz 00000000 (empty) (no description set)
    [EOF]
    ");

    let output = work_dir.run_jj(["log", "--no-graph", "-r@", "-Tdescription"]);
    insta::assert_snapshot!(output, @"
    Message from CLI

    Signed-off-by: test.user@example.com
    [EOF]
    ");

    // committer is properly set in the trailer
    let output = work_dir.run_jj(["describe", "--config=user.email=foo@bar.org"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Working copy  (@) now at: qpvuntsm 05ddee5c (empty) Message from CLI
    Parent commit (@-)      : zzzzzzzz 00000000 (empty) (no description set)
    [EOF]
    ");

    let output = work_dir.run_jj(["log", "--no-graph", "-r@", "-Tdescription"]);
    insta::assert_snapshot!(output, @"
    Message from CLI

    Signed-off-by: test.user@example.com
    Signed-off-by: foo@bar.org
    [EOF]
    ");

    // trailer is added with the expected committer in the editor
    std::fs::write(&edit_script, "dump editor0")?;
    let output = work_dir.run_jj(["describe", "--config", "user.email=foo@bar.net"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Working copy  (@) now at: qpvuntsm b7dafa2c (empty) Message from CLI
    Parent commit (@-)      : zzzzzzzz 00000000 (empty) (no description set)
    [EOF]
    ");

    insta::assert_snapshot!(
        std::fs::read_to_string(test_env.env_root().join("editor0"))?, @r#"
    Message from CLI

    Signed-off-by: test.user@example.com
    Signed-off-by: foo@bar.org
    Signed-off-by: foo@bar.net

    JJ: Change ID: qpvuntsm
    JJ:
    JJ: Lines starting with "JJ:" (like this one) will be removed.
    "#);

    let output = work_dir.run_jj(["log", "--no-graph", "-r@", "-Tdescription"]);
    insta::assert_snapshot!(output, @"
    Message from CLI

    Signed-off-by: test.user@example.com
    Signed-off-by: foo@bar.org
    Signed-off-by: foo@bar.net
    [EOF]
    ");

    // trailer is added added when editing an empty description
    work_dir.run_jj(["new"]).success();
    std::fs::write(&edit_script, "dump editor0")?;
    let output = work_dir.run_jj(["describe"]);
    insta::assert_snapshot!(output, @"
    ------- stderr -------
    Working copy  (@) now at: vruxwmqv b6148729 (empty) Signed-off-by: test.user@example.com
    Parent commit (@-)      : qpvuntsm b7dafa2c (empty) Message from CLI
    [EOF]
    ");

    let editor0 = std::fs::read_to_string(test_env.env_root().join("editor0"))?;
    insta::assert_snapshot!(
        format!("-----\n{editor0}-----\n"), @r#"
    -----


    Signed-off-by: test.user@example.com

    JJ: Change ID: vruxwmqv
    JJ:
    JJ: Lines starting with "JJ:" (like this one) will be removed.
    -----
    "#);
    Ok(())
}

#[must_use]
fn get_log_output(work_dir: &TestWorkDir) -> CommandOutput {
    let template = r#"commit_id.short() ++ " " ++ description"#;
    work_dir.run_jj(["log", "-T", template])
}