tests: use insta crate where appropriate

Thanks to @arxanas for the suggestion.

Cargo.lock

@@ -245,6 +245,19 @@ dependencies = [
  "yaml-rust",
 ]
 
+[[package]]
+name = "console"
+version = "0.15.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a28b32d32ca44b70c3e4acd7db1babf555fa026e385fb95f18028f88848b3c31"
+dependencies = [
+ "encode_unicode",
+ "libc",
+ "once_cell",
+ "terminal_size",
+ "winapi",
+]
+
 [[package]]
 name = "criterion"
 version = "0.3.5"
@@ -424,6 +437,12 @@ version = "1.6.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e78d4f1cc4ae33bbfc157ed5d5a5ef3bc29227303d595861deb238fcec4e9457"
 
+[[package]]
+name = "encode_unicode"
+version = "0.3.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a357d28ed41a50f9c765dbfe56cbc04a64e53e5fc58ba79fbc34c10ef3df831f"
+
 [[package]]
 name = "fake-simd"
 version = "0.1.2"
@@ -560,6 +579,20 @@ dependencies = [
  "unindent",
 ]
 
+[[package]]
+name = "insta"
+version = "1.13.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "30a7e1911532a662f6b08b68f884080850f2fd9544963c3ab23a5af42bda1eac"
+dependencies = [
+ "console",
+ "once_cell",
+ "serde 1.0.126",
+ "serde_json",
+ "serde_yaml",
+ "similar",
+]
+
 [[package]]
 name = "instant"
 version = "0.1.9"
@@ -624,6 +657,7 @@ dependencies = [
  "git2",
  "hex",
  "indoc",
+ "insta",
  "itertools",
  "jujutsu-lib",
  "maplit",
@@ -833,6 +867,12 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "once_cell"
+version = "1.10.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "87f3e037eac156d1775da914196f0f37741a274155e34a0b7e427c35d2a2ecb9"
+
 [[package]]
 name = "oorandom"
 version = "11.1.3"
@@ -1225,6 +1265,9 @@ name = "serde"
 version = "1.0.126"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ec7505abeacaec74ae4778d9d9328fe5a5d04253220a85c4ee022239fc996d03"
+dependencies = [
+ "serde_derive",
+]
 
 [[package]]
 name = "serde-hjson"
@@ -1270,6 +1313,18 @@ dependencies = [
  "serde 1.0.126",
 ]
 
+[[package]]
+name = "serde_yaml"
+version = "0.8.23"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a4a521f2940385c165a24ee286aa8599633d162077a54bdcae2a6fd5a7bfa7a0"
+dependencies = [
+ "indexmap",
+ "ryu",
+ "serde 1.0.126",
+ "yaml-rust",
+]
+
 [[package]]
 name = "sha-1"
 version = "0.8.2"
@@ -1282,6 +1337,12 @@ dependencies = [
  "opaque-debug",
 ]
 
+[[package]]
+name = "similar"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2e24979f63a11545f5f2c60141afe249d4f19f84581ea2138065e400941d83d3"
+
 [[package]]
 name = "smawk"
 version = "0.3.1"
@@ -1340,6 +1401,16 @@ dependencies = [
  "winapi-util",
 ]
 
+[[package]]
+name = "terminal_size"
+version = "0.1.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "633c1a546cee861a1a6d0dc69ebeca693bf4296661ba7852b9d21d159e0506df"
+dependencies = [
+ "libc",
+ "winapi",
+]
+
 [[package]]
 name = "termtree"
 version = "0.2.4"

Cargo.toml

@@ -35,6 +35,7 @@ criterion = "0.3.5"
 git2 = "0.13.25"
 hex = "0.4.3"
 indoc = "1.0.3"
+insta = "1.13.0"
 itertools = "0.10.3"
 jujutsu-lib = { version = "=0.2.0", path = "lib"}
 maplit = "1.0.2"

tests/smoke_test.rs

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-use jujutsu::testutils::TestEnvironment;
+use jujutsu::testutils::{get_stdout_string, TestEnvironment};
 
 #[test]
 fn smoke_test() {
@@ -24,15 +24,15 @@ fn smoke_test() {
 
     let repo_path = test_env.env_root().join("repo");
     // Check the output of `jj status` right after initializing repo
-    let expected_output = "Parent commit: 000000000000 
+    let assert = test_env
-Working copy : 1d1984a23811 
-The working copy is clean
-";
-    test_env
         .jj_cmd(&repo_path, &["status"])
         .assert()
-        .success()
+        .success();
-        .stdout(expected_output);
+    insta::assert_snapshot!(get_stdout_string(&assert), @r###"
+    Parent commit: 000000000000 
+    Working copy : 1d1984a23811 
+    The working copy is clean
+    "###);
 
     // Write some files and check the output of `jj status`
     std::fs::write(repo_path.join("file1"), "file1").unwrap();
@@ -40,41 +40,40 @@ The working copy is clean
     std::fs::write(repo_path.join("file3"), "file3").unwrap();
 
     // The working copy's ID should have changed
-    let expected_output = "Parent commit: 000000000000 
+    let assert = test_env
-Working copy : 5e60c5091e43 
-Working copy changes:
-A file1
-A file2
-A file3
-";
-    test_env
         .jj_cmd(&repo_path, &["status"])
         .assert()
-        .success()
+        .success();
-        .stdout(expected_output);
+    let stdout_string = get_stdout_string(&assert);
+    insta::assert_snapshot!(stdout_string, @r###"
+    Parent commit: 000000000000 
+    Working copy : 5e60c5091e43 
+    Working copy changes:
+    A file1
+    A file2
+    A file3
+    "###);
 
     // Running `jj status` again gives the same output
     test_env
         .jj_cmd(&repo_path, &["status"])
         .assert()
         .success()
-        .stdout(expected_output);
+        .stdout(stdout_string);
 
     // Add a commit description
-    let expected_output = "Working copy now at: 6f13b3e41065 add some files
+    let assert = test_env
-";
-    test_env
         .jj_cmd(&repo_path, &["describe", "-m", "add some files"])
         .assert()
-        .success()
+        .success();
-        .stdout(expected_output);
+    insta::assert_snapshot!(get_stdout_string(&assert), @"Working copy now at: 6f13b3e41065 add some files
+");
 
     // Close the commit
-    let expected_output = "Working copy now at: 6ff8a22d8ce1 
+    let assert = test_env
-";
-    test_env
         .jj_cmd(&repo_path, &["close"])
         .assert()
-        .success()
+        .success();
-        .stdout(expected_output);
+    insta::assert_snapshot!(get_stdout_string(&assert), @"Working copy now at: 6ff8a22d8ce1 
+");
 }

tests/test_global_opts.rs

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-use jujutsu::testutils::TestEnvironment;
+use jujutsu::testutils::{get_stdout_string, TestEnvironment};
 
 #[test]
 fn test_no_commit_working_copy() {
@@ -25,14 +25,16 @@ fn test_no_commit_working_copy() {
     let repo_path = test_env.env_root().join("repo");
 
     std::fs::write(repo_path.join("file"), "initial").unwrap();
-    let expected_output = "@ 1e9ff0ea7220c37a1d2c4aab153e238c12ff3cd0
+    let assert = test_env
-o 0000000000000000000000000000000000000000
-";
-    test_env
         .jj_cmd(&repo_path, &["log", "-T", "commit_id"])
         .assert()
-        .success()
+        .success();
-        .stdout(expected_output);
+    let stdout_string = get_stdout_string(&assert);
+    insta::assert_snapshot!(stdout_string, @r###"
+    @ 1e9ff0ea7220c37a1d2c4aab153e238c12ff3cd0
+    o 0000000000000000000000000000000000000000
+    "###);
+
 
     // Modify the file. With --no-commit-working-copy, we still get the same commit
     // ID.
@@ -44,35 +46,37 @@ o 0000000000000000000000000000000000000000
         )
         .assert()
         .success()
-        .stdout(expected_output);
+        .stdout(stdout_string);
 
     // But without --no-commit-working-copy, we get a new commit ID.
-    let expected_output = "@ cc12440b719c67fcd8c55848eb345f67b6e2d9f1
+    let assert = test_env
-o 0000000000000000000000000000000000000000
-";
-    test_env
         .jj_cmd(&repo_path, &["log", "-T", "commit_id"])
         .assert()
-        .success()
+        .success();
-        .stdout(expected_output);
+    insta::assert_snapshot!(get_stdout_string(&assert), @r###"
+    @ cc12440b719c67fcd8c55848eb345f67b6e2d9f1
+    o 0000000000000000000000000000000000000000
+    "###);
 }
 
 #[test]
 fn test_repo_arg_with_init() {
     let test_env = TestEnvironment::default();
-    test_env
+    let assert = test_env
         .jj_cmd(test_env.env_root(), &["init", "-R=.", "repo"])
         .assert()
-        .failure()
+        .failure();
-        .stdout("Error: '--repository' cannot be used with 'init'\n");
+    insta::assert_snapshot!(get_stdout_string(&assert), @"Error: '--repository' cannot be used with 'init'
+");
 }
 
 #[test]
 fn test_repo_arg_with_git_clone() {
     let test_env = TestEnvironment::default();
-    test_env
+    let assert = test_env
         .jj_cmd(test_env.env_root(), &["git", "clone", "-R=.", "remote"])
         .assert()
-        .failure()
+        .failure();
-        .stdout("Error: '--repository' cannot be used with 'git clone'\n");
+    insta::assert_snapshot!(get_stdout_string(&assert), @"Error: '--repository' cannot be used with 'git clone'
+");
 }