// 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::Path;

use crate::common::TestEnvironment;

#[test]
fn test_squash() {
    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");

    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "a"]);
    std::fs::write(repo_path.join("file1"), "a\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "b"]);
    std::fs::write(repo_path.join("file1"), "b\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "c"]);
    std::fs::write(repo_path.join("file1"), "c\n").unwrap();
    // Test the setup
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  382c9bad7d42 c
    ◉  d5d59175b481 b
    ◉  184ddbcce5a9 a
    ◉  000000000000
    "###);

    // Squashes the working copy into the parent by default
    let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["squash"]);
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Working copy now at: vruxwmqv f7bb78d8 (empty) (no description set)
    Parent commit      : kkmpptxz 59f44460 b c | (no description set)
    "###);
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  f7bb78d8da62
    ◉  59f4446070a0 b c
    ◉  184ddbcce5a9 a
    ◉  000000000000
    "###);
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file1"]);
    insta::assert_snapshot!(stdout, @r###"
    c
    "###);

    // Can squash a given commit into its parent
    test_env.jj_cmd_ok(&repo_path, &["undo"]);
    let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["squash", "-r", "b"]);
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Rebased 1 descendant commits
    Working copy now at: mzvwutvl 1d70f50a c | (no description set)
    Parent commit      : qpvuntsm 9146bcc8 a b | (no description set)
    "###);
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  1d70f50afa6d c
    ◉  9146bcc8d996 a b
    ◉  000000000000
    "###);
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file1", "-r", "b"]);
    insta::assert_snapshot!(stdout, @r###"
    b
    "###);
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file1"]);
    insta::assert_snapshot!(stdout, @r###"
    c
    "###);

    // Cannot squash a merge commit (because it's unclear which parent it should go
    // into)
    test_env.jj_cmd_ok(&repo_path, &["undo"]);
    test_env.jj_cmd_ok(&repo_path, &["edit", "b"]);
    test_env.jj_cmd_ok(&repo_path, &["new"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "d"]);
    std::fs::write(repo_path.join("file2"), "d\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new", "c", "d"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "e"]);
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @    41219719ab5f e
    ├─╮
    │ ◉  f86e2b3af3e3 d
    ◉ │  382c9bad7d42 c
    ├─╯
    ◉  d5d59175b481 b
    ◉  184ddbcce5a9 a
    ◉  000000000000
    "###);
    let stderr = test_env.jj_cmd_failure(&repo_path, &["squash"]);
    insta::assert_snapshot!(stderr, @r###"
    Error: Cannot squash merge commits
    "###);

    // Can squash into a merge commit
    test_env.jj_cmd_ok(&repo_path, &["new", "e"]);
    std::fs::write(repo_path.join("file1"), "e\n").unwrap();
    let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["squash"]);
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Working copy now at: xlzxqlsl b50b843d (empty) (no description set)
    Parent commit      : nmzmmopx 338cbc05 e | (no description set)
    "###);
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  b50b843d8555
    ◉    338cbc05e4e6 e
    ├─╮
    │ ◉  f86e2b3af3e3 d
    ◉ │  382c9bad7d42 c
    ├─╯
    ◉  d5d59175b481 b
    ◉  184ddbcce5a9 a
    ◉  000000000000
    "###);
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file1", "-r", "e"]);
    insta::assert_snapshot!(stdout, @r###"
    e
    "###);
}

#[test]
fn test_squash_partial() {
    let mut 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");

    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "a"]);
    std::fs::write(repo_path.join("file1"), "a\n").unwrap();
    std::fs::write(repo_path.join("file2"), "a\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "b"]);
    std::fs::write(repo_path.join("file1"), "b\n").unwrap();
    std::fs::write(repo_path.join("file2"), "b\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "c"]);
    std::fs::write(repo_path.join("file1"), "c\n").unwrap();
    std::fs::write(repo_path.join("file2"), "c\n").unwrap();
    // Test the setup
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  a0b1a272ebc4 c
    ◉  d117da276a0f b
    ◉  54d3c1c0e9fd a
    ◉  000000000000
    "###);

    // If we don't make any changes in the diff-editor, the whole change is moved
    // into the parent
    let edit_script = test_env.set_up_fake_diff_editor();
    let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["squash", "-r", "b", "-i"]);
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Rebased 1 descendant commits
    Working copy now at: mzvwutvl 3c633226 c | (no description set)
    Parent commit      : qpvuntsm 38ffd8b9 a b | (no description set)
    "###);
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  3c6332267ea8 c
    ◉  38ffd8b98578 a b
    ◉  000000000000
    "###);
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file1", "-r", "a"]);
    insta::assert_snapshot!(stdout, @r###"
    b
    "###);

    // Can squash only some changes in interactive mode
    test_env.jj_cmd_ok(&repo_path, &["undo"]);
    std::fs::write(&edit_script, "reset file1").unwrap();
    let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["squash", "-r", "b", "-i"]);
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Rebased 2 descendant commits
    Working copy now at: mzvwutvl 57c3cf20 c | (no description set)
    Parent commit      : kkmpptxz c4925e01 b | (no description set)
    "###);
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  57c3cf20d0b1 c
    ◉  c4925e01d298 b
    ◉  1fc159063ed3 a
    ◉  000000000000
    "###);
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file1", "-r", "a"]);
    insta::assert_snapshot!(stdout, @r###"
    a
    "###);
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file2", "-r", "a"]);
    insta::assert_snapshot!(stdout, @r###"
    b
    "###);
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file1", "-r", "b"]);
    insta::assert_snapshot!(stdout, @r###"
    b
    "###);
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file2", "-r", "b"]);
    insta::assert_snapshot!(stdout, @r###"
    b
    "###);

    // Can squash only some changes in non-interactive mode
    test_env.jj_cmd_ok(&repo_path, &["undo"]);
    // Clear the script so we know it won't be used even without -i
    std::fs::write(&edit_script, "").unwrap();
    let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["squash", "-r", "b", "file2"]);
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Rebased 2 descendant commits
    Working copy now at: mzvwutvl 64d7ad7c c | (no description set)
    Parent commit      : kkmpptxz 60a26452 b | (no description set)
    "###);
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  64d7ad7c43c1 c
    ◉  60a264527aee b
    ◉  7314692d32e3 a
    ◉  000000000000
    "###);
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file1", "-r", "a"]);
    insta::assert_snapshot!(stdout, @r###"
    a
    "###);
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file2", "-r", "a"]);
    insta::assert_snapshot!(stdout, @r###"
    b
    "###);
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file1", "-r", "b"]);
    insta::assert_snapshot!(stdout, @r###"
    b
    "###);
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file2", "-r", "b"]);
    insta::assert_snapshot!(stdout, @r###"
    b
    "###);

    // If we specify only a non-existent file, then nothing changes.
    test_env.jj_cmd_ok(&repo_path, &["undo"]);
    let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["squash", "-r", "b", "nonexistent"]);
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Nothing changed.
    "###);

    // We get a warning if we pass a positional argument that looks like a revset
    test_env.jj_cmd_ok(&repo_path, &["undo"]);
    let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["squash", "b"]);
    insta::assert_snapshot!(stderr, @r###"
    Warning: The argument "b" is being interpreted as a path. To specify a revset, pass -r "b" instead.
    Nothing changed.
    "###);
    insta::assert_snapshot!(stdout, @"");
}

#[test]
fn test_squash_from_to() {
    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");

    // Create history like this:
    // F
    // |
    // E C
    // | |
    // D B
    // |/
    // A
    //
    // When moving changes between e.g. C and F, we should not get unrelated changes
    // from B and D.
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "a"]);
    std::fs::write(repo_path.join("file1"), "a\n").unwrap();
    std::fs::write(repo_path.join("file2"), "a\n").unwrap();
    std::fs::write(repo_path.join("file3"), "a\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "b"]);
    std::fs::write(repo_path.join("file3"), "b\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "c"]);
    std::fs::write(repo_path.join("file1"), "c\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["edit", "a"]);
    test_env.jj_cmd_ok(&repo_path, &["new"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "d"]);
    std::fs::write(repo_path.join("file3"), "d\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "e"]);
    std::fs::write(repo_path.join("file2"), "e\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "f"]);
    std::fs::write(repo_path.join("file2"), "f\n").unwrap();
    // Test the setup
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  a847ab4967fe f
    ◉  c2f9de87325d e
    ◉  e0dac715116f d
    │ ◉  59597b34a0d8 c
    │ ◉  12d6103dc0c8 b
    ├─╯
    ◉  b7b767179c44 a
    ◉  000000000000
    "###);

    // Errors out if source and destination are the same
    let stderr = test_env.jj_cmd_failure(&repo_path, &["squash", "--into", "@"]);
    insta::assert_snapshot!(stderr, @r###"
    Error: Source and destination cannot be the same
    "###);

    // Can squash from sibling, which results in the source being abandoned
    let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["squash", "--from", "c"]);
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Working copy now at: kmkuslsw b902d1dd f | (no description set)
    Parent commit      : znkkpsqq c2f9de87 e | (no description set)
    Added 0 files, modified 1 files, removed 0 files
    "###);
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  b902d1dd59d9 f
    ◉  c2f9de87325d e
    ◉  e0dac715116f d
    │ ◉  12d6103dc0c8 b c
    ├─╯
    ◉  b7b767179c44 a
    ◉  000000000000
    "###);
    // The change from the source has been applied
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file1"]);
    insta::assert_snapshot!(stdout, @r###"
    c
    "###);
    // File `file2`, which was not changed in source, is unchanged
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file2"]);
    insta::assert_snapshot!(stdout, @r###"
    f
    "###);

    // Can squash from ancestor
    test_env.jj_cmd_ok(&repo_path, &["undo"]);
    let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["squash", "--from", "@--"]);
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Working copy now at: kmkuslsw cfc5eb87 f | (no description set)
    Parent commit      : znkkpsqq 4dc7c279 e | (no description set)
    "###);
    // The change has been removed from the source (the change pointed to by 'd'
    // became empty and was abandoned)
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  cfc5eb876eb1 f
    ◉  4dc7c27994bd e
    │ ◉  59597b34a0d8 c
    │ ◉  12d6103dc0c8 b
    ├─╯
    ◉  b7b767179c44 a d
    ◉  000000000000
    "###);
    // The change from the source has been applied (the file contents were already
    // "f", as is typically the case when moving changes from an ancestor)
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file2"]);
    insta::assert_snapshot!(stdout, @r###"
    f
    "###);

    // Can squash from descendant
    test_env.jj_cmd_ok(&repo_path, &["undo"]);
    let (stdout, stderr) =
        test_env.jj_cmd_ok(&repo_path, &["squash", "--from", "e", "--into", "d"]);
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Rebased 1 descendant commits
    Working copy now at: kmkuslsw 6de62c22 f | (no description set)
    Parent commit      : vruxwmqv 32196a11 d e | (no description set)
    "###);
    // The change has been removed from the source (the change pointed to by 'e'
    // became empty and was abandoned)
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  6de62c22fa07 f
    ◉  32196a117ee3 d e
    │ ◉  59597b34a0d8 c
    │ ◉  12d6103dc0c8 b
    ├─╯
    ◉  b7b767179c44 a
    ◉  000000000000
    "###);
    // The change from the source has been applied
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file2", "-r", "d"]);
    insta::assert_snapshot!(stdout, @r###"
    e
    "###);
}

#[test]
fn test_squash_from_to_partial() {
    let mut 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");

    // Create history like this:
    //   C
    //   |
    // D B
    // |/
    // A
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "a"]);
    std::fs::write(repo_path.join("file1"), "a\n").unwrap();
    std::fs::write(repo_path.join("file2"), "a\n").unwrap();
    std::fs::write(repo_path.join("file3"), "a\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "b"]);
    std::fs::write(repo_path.join("file3"), "b\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "c"]);
    std::fs::write(repo_path.join("file1"), "c\n").unwrap();
    std::fs::write(repo_path.join("file2"), "c\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["edit", "a"]);
    test_env.jj_cmd_ok(&repo_path, &["new"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "d"]);
    std::fs::write(repo_path.join("file3"), "d\n").unwrap();
    // Test the setup
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  e0dac715116f d
    │ ◉  087591be5a01 c
    │ ◉  12d6103dc0c8 b
    ├─╯
    ◉  b7b767179c44 a
    ◉  000000000000
    "###);

    let edit_script = test_env.set_up_fake_diff_editor();

    // If we don't make any changes in the diff-editor, the whole change is moved
    let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["squash", "-i", "--from", "c"]);
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Working copy now at: vruxwmqv 987bcfb2 d | (no description set)
    Parent commit      : qpvuntsm b7b76717 a | (no description set)
    Added 0 files, modified 2 files, removed 0 files
    "###);
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  987bcfb2eb62 d
    │ ◉  12d6103dc0c8 b c
    ├─╯
    ◉  b7b767179c44 a
    ◉  000000000000
    "###);
    // The changes from the source has been applied
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file1"]);
    insta::assert_snapshot!(stdout, @r###"
    c
    "###);
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file2"]);
    insta::assert_snapshot!(stdout, @r###"
    c
    "###);
    // File `file3`, which was not changed in source, is unchanged
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file3"]);
    insta::assert_snapshot!(stdout, @r###"
    d
    "###);

    // Can squash only part of the change in interactive mode
    test_env.jj_cmd_ok(&repo_path, &["undo"]);
    std::fs::write(&edit_script, "reset file2").unwrap();
    let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["squash", "-i", "--from", "c"]);
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Working copy now at: vruxwmqv 576244e8 d | (no description set)
    Parent commit      : qpvuntsm b7b76717 a | (no description set)
    Added 0 files, modified 1 files, removed 0 files
    "###);
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  576244e87883 d
    │ ◉  6f486f2f4539 c
    │ ◉  12d6103dc0c8 b
    ├─╯
    ◉  b7b767179c44 a
    ◉  000000000000
    "###);
    // The selected change from the source has been applied
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file1"]);
    insta::assert_snapshot!(stdout, @r###"
    c
    "###);
    // The unselected change from the source has not been applied
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file2"]);
    insta::assert_snapshot!(stdout, @r###"
    a
    "###);
    // File `file3`, which was changed in source's parent, is unchanged
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file3"]);
    insta::assert_snapshot!(stdout, @r###"
    d
    "###);

    // Can squash only part of the change from a sibling in non-interactive mode
    test_env.jj_cmd_ok(&repo_path, &["undo"]);
    // Clear the script so we know it won't be used
    std::fs::write(&edit_script, "").unwrap();
    let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["squash", "--from", "c", "file1"]);
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Working copy now at: vruxwmqv 5b407c24 d | (no description set)
    Parent commit      : qpvuntsm b7b76717 a | (no description set)
    Added 0 files, modified 1 files, removed 0 files
    "###);
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  5b407c249fa7 d
    │ ◉  724d64da1487 c
    │ ◉  12d6103dc0c8 b
    ├─╯
    ◉  b7b767179c44 a
    ◉  000000000000
    "###);
    // The selected change from the source has been applied
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file1"]);
    insta::assert_snapshot!(stdout, @r###"
    c
    "###);
    // The unselected change from the source has not been applied
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file2"]);
    insta::assert_snapshot!(stdout, @r###"
    a
    "###);
    // File `file3`, which was changed in source's parent, is unchanged
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file3"]);
    insta::assert_snapshot!(stdout, @r###"
    d
    "###);

    // Can squash only part of the change from a descendant in non-interactive mode
    test_env.jj_cmd_ok(&repo_path, &["undo"]);
    // Clear the script so we know it won't be used
    std::fs::write(&edit_script, "").unwrap();
    let (stdout, stderr) = test_env.jj_cmd_ok(
        &repo_path,
        &["squash", "--from", "c", "--into", "b", "file1"],
    );
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Rebased 1 descendant commits
    "###);
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    ◉  d2a587ae205d c
    ◉  a53394306362 b
    │ @  e0dac715116f d
    ├─╯
    ◉  b7b767179c44 a
    ◉  000000000000
    "###);
    // The selected change from the source has been applied
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file1", "-r", "b"]);
    insta::assert_snapshot!(stdout, @r###"
    c
    "###);
    // The unselected change from the source has not been applied
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "file2", "-r", "b"]);
    insta::assert_snapshot!(stdout, @r###"
    a
    "###);

    // If we specify only a non-existent file, then nothing changes.
    test_env.jj_cmd_ok(&repo_path, &["undo"]);
    let (stdout, stderr) =
        test_env.jj_cmd_ok(&repo_path, &["squash", "--from", "c", "nonexistent"]);
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Nothing changed.
    "###);
}

#[test]
fn test_squash_from_multiple() {
    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");

    // Create history like this:
    //   F
    //   |
    //   E
    //  /|\
    // B C D
    //  \|/
    //   A
    let file = repo_path.join("file");
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "a"]);
    std::fs::write(&file, "a\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "b"]);
    std::fs::write(&file, "b\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new", "@-"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "c"]);
    std::fs::write(&file, "c\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new", "@-"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "d"]);
    std::fs::write(&file, "d\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new", "all:visible_heads()"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "e"]);
    std::fs::write(&file, "e\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "f"]);
    std::fs::write(&file, "f\n").unwrap();
    // Test the setup
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  94e57ecb8d4f f
    ◉      78ed28eb87b8 e
    ├─┬─╮
    │ │ ◉  35e764e4357c b
    │ ◉ │  02a128cd4344 c
    │ ├─╯
    ◉ │  aaf7b53a1b64 d
    ├─╯
    ◉  3b1673b6370c a
    ◉  000000000000
    "###);

    // Squash a few commits sideways
    let (stdout, stderr) =
        test_env.jj_cmd_ok(&repo_path, &["squash", "--from=b", "--from=c", "--into=d"]);
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Rebased 2 descendant commits
    New conflicts appeared in these commits:
      yqosqzyt 98759deb d | (conflict) (no description set)
    To resolve the conflicts, start by updating to it:
      jj new yqosqzytrlsw
    Then use `jj resolve`, or edit the conflict markers in the file directly.
    Once the conflicts are resolved, you may want inspect the result with `jj diff`.
    Then run `jj squash` to move the resolution into the conflicted commit.
    Working copy now at: kpqxywon 3e25ee21 f | (no description set)
    Parent commit      : yostqsxw abb5a4ea e | (no description set)
    "###);
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  3e25ee211f3f f
    ◉    abb5a4ea1222 e
    ├─╮
    ◉ │  98759debcee5 d
    ├─╯
    ◉  3b1673b6370c a b c
    ◉  000000000000
    "###);
    // The changes from the sources have been applied
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "-r=d", "file"]);
    insta::assert_snapshot!(stdout, @r###"
    <<<<<<< Conflict 1 of 1
    %%%%%%% Changes from base #1 to side #1
    -a
    +d
    %%%%%%% Changes from base #2 to side #2
    -a
    +b
    +++++++ Contents of side #3
    c
    >>>>>>> Conflict 1 of 1 ends
    "###);

    // Squash a few commits up an down
    test_env.jj_cmd_ok(&repo_path, &["undo"]);
    let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["squash", "--from=b|c|f", "--into=e"]);
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Rebased 1 descendant commits
    Working copy now at: xznxytkn 6a670d1a (empty) (no description set)
    Parent commit      : yostqsxw c1293ff7 e f | (no description set)
    "###);
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  6a670d1ac76e
    ◉    c1293ff7be51 e f
    ├─╮
    ◉ │  aaf7b53a1b64 d
    ├─╯
    ◉  3b1673b6370c a b c
    ◉  000000000000
    "###);
    // The changes from the sources have been applied to the destination
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "-r=e", "file"]);
    insta::assert_snapshot!(stdout, @r###"
    f
    "###);

    // Empty squash shouldn't crash
    let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["squash", "--from=none()"]);
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Nothing changed.
    "###);
}

#[test]
fn test_squash_from_multiple_partial() {
    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");

    // Create history like this:
    //   F
    //   |
    //   E
    //  /|\
    // B C D
    //  \|/
    //   A
    let file1 = repo_path.join("file1");
    let file2 = repo_path.join("file2");
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "a"]);
    std::fs::write(&file1, "a\n").unwrap();
    std::fs::write(&file2, "a\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "b"]);
    std::fs::write(&file1, "b\n").unwrap();
    std::fs::write(&file2, "b\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new", "@-"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "c"]);
    std::fs::write(&file1, "c\n").unwrap();
    std::fs::write(&file2, "c\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new", "@-"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "d"]);
    std::fs::write(&file1, "d\n").unwrap();
    std::fs::write(&file2, "d\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new", "all:visible_heads()"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "e"]);
    std::fs::write(&file1, "e\n").unwrap();
    std::fs::write(&file2, "e\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new"]);
    test_env.jj_cmd_ok(&repo_path, &["branch", "create", "f"]);
    std::fs::write(&file1, "f\n").unwrap();
    std::fs::write(&file2, "f\n").unwrap();
    // Test the setup
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  30980b9045f7 f
    ◉      5326a04aac1f e
    ├─┬─╮
    │ │ ◉  d117da276a0f b
    │ ◉ │  93a7bfff61e7 c
    │ ├─╯
    ◉ │  763809ca0131 d
    ├─╯
    ◉  54d3c1c0e9fd a
    ◉  000000000000
    "###);

    // Partially squash a few commits sideways
    let (stdout, stderr) =
        test_env.jj_cmd_ok(&repo_path, &["squash", "--from=b|c", "--into=d", "file1"]);
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Rebased 2 descendant commits
    New conflicts appeared in these commits:
      yqosqzyt b91b1157 d | (conflict) (no description set)
    To resolve the conflicts, start by updating to it:
      jj new yqosqzytrlsw
    Then use `jj resolve`, or edit the conflict markers in the file directly.
    Once the conflicts are resolved, you may want inspect the result with `jj diff`.
    Then run `jj squash` to move the resolution into the conflicted commit.
    Working copy now at: kpqxywon 056dc38b f | (no description set)
    Parent commit      : yostqsxw 45069475 e | (no description set)
    "###);
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  056dc38bf286 f
    ◉      450694753699 e
    ├─┬─╮
    │ │ ◉  450d1499c1ae b
    │ ◉ │  14b44bf0473c c
    │ ├─╯
    ◉ │  b91b11575906 d
    ├─╯
    ◉  54d3c1c0e9fd a
    ◉  000000000000
    "###);
    // The selected changes have been removed from the sources
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "-r=b", "file1"]);
    insta::assert_snapshot!(stdout, @r###"
    a
    "###);
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "-r=c", "file1"]);
    insta::assert_snapshot!(stdout, @r###"
    a
    "###);
    // The selected changes from the sources have been applied
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "-r=d", "file1"]);
    insta::assert_snapshot!(stdout, @r###"
    <<<<<<< Conflict 1 of 1
    %%%%%%% Changes from base #1 to side #1
    -a
    +d
    %%%%%%% Changes from base #2 to side #2
    -a
    +b
    +++++++ Contents of side #3
    c
    >>>>>>> Conflict 1 of 1 ends
    "###);
    // The unselected change from the sources have not been applied to the
    // destination
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "-r=d", "file2"]);
    insta::assert_snapshot!(stdout, @r###"
    d
    "###);

    // Partially squash a few commits up an down
    test_env.jj_cmd_ok(&repo_path, &["undo"]);
    let (stdout, stderr) =
        test_env.jj_cmd_ok(&repo_path, &["squash", "--from=b|c|f", "--into=e", "file1"]);
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Rebased 1 descendant commits
    Working copy now at: kpqxywon 3b7559b8 f | (no description set)
    Parent commit      : yostqsxw a3b1714c e | (no description set)
    "###);
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  3b7559b89a57 f
    ◉      a3b1714cdfb2 e
    ├─┬─╮
    │ │ ◉  867efb38e801 b
    │ ◉ │  84dcb3d4b3eb c
    │ ├─╯
    ◉ │  763809ca0131 d
    ├─╯
    ◉  54d3c1c0e9fd a
    ◉  000000000000
    "###);
    // The selected changes have been removed from the sources
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "-r=b", "file1"]);
    insta::assert_snapshot!(stdout, @r###"
    a
    "###);
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "-r=c", "file1"]);
    insta::assert_snapshot!(stdout, @r###"
    a
    "###);
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "-r=f", "file1"]);
    insta::assert_snapshot!(stdout, @r###"
    f
    "###);
    // The selected changes from the sources have been applied to the destination
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "-r=e", "file1"]);
    insta::assert_snapshot!(stdout, @r###"
    f
    "###);
    // The unselected changes from the sources have not been applied
    let stdout = test_env.jj_cmd_success(&repo_path, &["file", "show", "-r=d", "file2"]);
    insta::assert_snapshot!(stdout, @r###"
    d
    "###);
}

#[test]
fn test_squash_from_multiple_partial_no_op() {
    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");

    // Create history like this:
    // B C D
    //  \|/
    //   A
    let file_a = repo_path.join("a");
    let file_b = repo_path.join("b");
    let file_c = repo_path.join("c");
    let file_d = repo_path.join("d");
    test_env.jj_cmd_ok(&repo_path, &["describe", "-m=a"]);
    std::fs::write(file_a, "a\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new", "-m=b"]);
    std::fs::write(file_b, "b\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new", "@-", "-m=c"]);
    std::fs::write(file_c, "c\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new", "@-", "-m=d"]);
    std::fs::write(file_d, "d\n").unwrap();
    // Test the setup
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  b37ca1ee3306 d
    │ ◉  f40b442af3e8 c
    ├─╯
    │ ◉  b73077b08c59 b
    ├─╯
    ◉  2443ea76b0b1 a
    ◉  000000000000
    "###);

    // Source commits that didn't match the paths are not rewritten
    let (stdout, stderr) = test_env.jj_cmd_ok(
        &repo_path,
        &["squash", "--from=@-+ ~ @", "--into=@", "-m=d", "b"],
    );
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Working copy now at: mzvwutvl e178068a d
    Parent commit      : qpvuntsm 2443ea76 a
    Added 1 files, modified 0 files, removed 0 files
    "###);
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  e178068add8c d
    │ ◉  f40b442af3e8 c
    ├─╯
    ◉  2443ea76b0b1 a
    ◉  000000000000
    "###);
    let stdout = test_env.jj_cmd_success(
        &repo_path,
        &[
            "obslog",
            "-T",
            r#"separate(" ", commit_id.short(), description)"#,
        ],
    );
    insta::assert_snapshot!(stdout, @r###"
    @    e178068add8c d
    ├─╮
    ◉ │  b37ca1ee3306 d
    ◉ │  1d9eb34614c9 d
      ◉  b73077b08c59 b
      ◉  a786561e909f b
    "###);

    // If no source commits match the paths, then the whole operation is a no-op
    test_env.jj_cmd_ok(&repo_path, &["undo"]);
    let (stdout, stderr) = test_env.jj_cmd_ok(
        &repo_path,
        &["squash", "--from=@-+ ~ @", "--into=@", "-m=d", "a"],
    );
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Nothing changed.
    "###);
    insta::assert_snapshot!(get_log_output(&test_env, &repo_path), @r###"
    @  b37ca1ee3306 d
    │ ◉  f40b442af3e8 c
    ├─╯
    │ ◉  b73077b08c59 b
    ├─╯
    ◉  2443ea76b0b1 a
    ◉  000000000000
    "###);
}

fn get_log_output(test_env: &TestEnvironment, repo_path: &Path) -> String {
    let template = r#"separate(" ", commit_id.short(), branches, description)"#;
    test_env.jj_cmd_success(repo_path, &["log", "-T", template])
}

#[test]
fn test_squash_description() {
    let mut 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 edit_script = test_env.set_up_fake_editor();
    std::fs::write(&edit_script, r#"fail"#).unwrap();

    // If both descriptions are empty, the resulting description is empty
    std::fs::write(repo_path.join("file1"), "a\n").unwrap();
    std::fs::write(repo_path.join("file2"), "a\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["new"]);
    std::fs::write(repo_path.join("file1"), "b\n").unwrap();
    std::fs::write(repo_path.join("file2"), "b\n").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["squash"]);
    insta::assert_snapshot!(get_description(&test_env, &repo_path, "@-"), @"");

    // If the destination's description is empty and the source's description is
    // non-empty, the resulting description is from the source
    test_env.jj_cmd_ok(&repo_path, &["undo"]);
    test_env.jj_cmd_ok(&repo_path, &["describe", "-m", "source"]);
    test_env.jj_cmd_ok(&repo_path, &["squash"]);
    insta::assert_snapshot!(get_description(&test_env, &repo_path, "@-"), @r###"
    source
    "###);

    // If the destination description is non-empty and the source's description is
    // empty, the resulting description is from the destination
    test_env.jj_cmd_ok(&repo_path, &["op", "restore", "@--"]);
    test_env.jj_cmd_ok(&repo_path, &["describe", "@-", "-m", "destination"]);
    test_env.jj_cmd_ok(&repo_path, &["squash"]);
    insta::assert_snapshot!(get_description(&test_env, &repo_path, "@-"), @r###"
    destination
    "###);

    // An explicit description on the command-line overrides this
    test_env.jj_cmd_ok(&repo_path, &["undo"]);
    test_env.jj_cmd_ok(&repo_path, &["squash", "-m", "custom"]);
    insta::assert_snapshot!(get_description(&test_env, &repo_path, "@-"), @r###"
    custom
    "###);

    // If both descriptions were non-empty, we get asked for a combined description
    test_env.jj_cmd_ok(&repo_path, &["undo"]);
    test_env.jj_cmd_ok(&repo_path, &["describe", "-m", "source"]);
    std::fs::write(&edit_script, "dump editor0").unwrap();
    test_env.jj_cmd_ok(&repo_path, &["squash"]);
    insta::assert_snapshot!(get_description(&test_env, &repo_path, "@-"), @r###"
    destination

    source
    "###);
    insta::assert_snapshot!(
        std::fs::read_to_string(test_env.env_root().join("editor0")).unwrap(), @r###"
    JJ: Enter a description for the combined commit.
    JJ: Description from the destination commit:
    destination

    JJ: Description from source commit:
    source

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

    // An explicit description on the command-line overrides prevents launching an
    // editor
    test_env.jj_cmd_ok(&repo_path, &["undo"]);
    test_env.jj_cmd_ok(&repo_path, &["squash", "-m", "custom"]);
    insta::assert_snapshot!(get_description(&test_env, &repo_path, "@-"), @r###"
    custom
    "###);

    // If the source's *content* doesn't become empty, then the source remains and
    // both descriptions are unchanged
    test_env.jj_cmd_ok(&repo_path, &["undo"]);
    test_env.jj_cmd_ok(&repo_path, &["squash", "file1"]);
    insta::assert_snapshot!(get_description(&test_env, &repo_path, "@-"), @r###"
    destination
    "###);
    insta::assert_snapshot!(get_description(&test_env, &repo_path, "@"), @r###"
    source
    "###);
}

#[test]
fn test_squash_empty() {
    let mut 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");

    test_env.jj_cmd_ok(&repo_path, &["commit", "-m", "parent"]);

    let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["squash"]);
    insta::assert_snapshot!(stdout, @"");
    insta::assert_snapshot!(stderr, @r###"
    Working copy now at: kkmpptxz adece6e8 (empty) (no description set)
    Parent commit      : qpvuntsm 5076fc41 (empty) parent
    "###);
    insta::assert_snapshot!(get_description(&test_env, &repo_path, "@-"), @r###"
    parent
    "###);

    test_env.jj_cmd_ok(&repo_path, &["describe", "-m", "child"]);
    test_env.set_up_fake_editor();
    test_env.jj_cmd_ok(&repo_path, &["squash"]);
    insta::assert_snapshot!(get_description(&test_env, &repo_path, "@-"), @r###"
    parent

    child
    "###);
}

#[test]
fn test_squash_use_destination_message() {
    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");

    test_env.jj_cmd_ok(&repo_path, &["commit", "-m=a"]);
    test_env.jj_cmd_ok(&repo_path, &["commit", "-m=b"]);
    test_env.jj_cmd_ok(&repo_path, &["describe", "-m=c"]);
    // Test the setup
    insta::assert_snapshot!(get_log_output_with_description(&test_env, &repo_path), @r###"
    @  8aac283daeac c
    ◉  017c7f689ed7 b
    ◉  d8d5f980a897 a
    ◉  000000000000
    "###);

    // Squash the current revision using the short name for the option.
    test_env.jj_cmd_ok(&repo_path, &["squash", "-u"]);
    insta::assert_snapshot!(get_log_output_with_description(&test_env, &repo_path), @r###"
    @  fd33e4bc332b
    ◉  3a17aa5dcce9 b
    ◉  d8d5f980a897 a
    ◉  000000000000
    "###);

    // Undo and squash again, but this time squash both "b" and "c" into "a".
    test_env.jj_cmd_ok(&repo_path, &["undo"]);
    test_env.jj_cmd_ok(
        &repo_path,
        &[
            "squash",
            "--use-destination-message",
            "--from",
            "description(b)::",
            "--into",
            "description(a)",
        ],
    );
    insta::assert_snapshot!(get_log_output_with_description(&test_env, &repo_path), @r###"
    @  7c832accbf60
    ◉  688660377651 a
    ◉  000000000000
    "###);
}

// The --use-destination-message and --message options are incompatible.
#[test]
fn test_squash_use_destination_message_and_message_mutual_exclusion() {
    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");
    test_env.jj_cmd_ok(&repo_path, &["commit", "-m=a"]);
    test_env.jj_cmd_ok(&repo_path, &["describe", "-m=b"]);
    insta::assert_snapshot!(test_env.jj_cmd_cli_error(
        &repo_path,
        &[
            "squash",
            "--message=123",
            "--use-destination-message",
        ],
    ), @r###"
    error: the argument '--message <MESSAGE>' cannot be used with '--use-destination-message'

    Usage: jj squash --message <MESSAGE> [PATHS]...

    For more information, try '--help'.
    "###);
}

fn get_description(test_env: &TestEnvironment, repo_path: &Path, rev: &str) -> String {
    test_env.jj_cmd_success(
        repo_path,
        &["log", "--no-graph", "-T", "description", "-r", rev],
    )
}

fn get_log_output_with_description(test_env: &TestEnvironment, repo_path: &Path) -> String {
    let template = r#"separate(" ", commit_id.short(), description)"#;
    test_env.jj_cmd_success(repo_path, &["log", "-T", template])
}