DeltaTest improvements (#876)

* DeltaTest improvements

- Added .expect_contains(), .expect_raw_contains(), and
  .expect_contains_once() member functions to DeltaTestOutput.
  These functions also output some helpful debug info when the
  assert fails.
- Separated .with_config_and_input() into .with_config() and (the
  tweaked) .with_input().
- Made .with_config() create a DeltaTest object (like .with() does).
- Renamed .with() as .with_args().
- Moved .explain_ansi() from DeltaTestOutput to DeltaTest, which must
  now be called prior to .with_input() since the latter stashes off both
  the raw_output & the processed output in the object.
- Changed .expect() and .expect_skip() to return Self so that they can
  continue a chain of multiple expect calls (e.g. a series of partial
  matches with different skip values).
- The processed output text can be accessed via `test_obj.output` (see
  also `test_obj.raw_output`).
- Renamed .expect_skip() to .expect_after_skip().
- Changed .expect() to start at the first line.
- Added .expect_after_header() that works like the old .expect().
- Renamed lines_match() to assert_lines_match() and made it match all
  lines (no skip number).
- Added assert_lines_match_after_skip() to work like the old
  lines_match() function, but with the .expect_after_skip() arg order.
- Converted some old-style tests into DeltaTest style tests.
- Renamed set_cfg as set_config

1 files changed, 62 insertions, 95 deletions

diff --git a/src/tests/test_example_diffs.rs b/src/tests/test_example_diffs.rs
index a135a9b..6e0c542 100644
--- a/src/tests/test_example_diffs.rs
+++ b/src/tests/test_example_diffs.rs
@@ -7,67 +7,53 @@ mod tests {
     use crate::style;
     use crate::tests::ansi_test_utils::ansi_test_utils;
     use crate::tests::integration_test_utils;
-    use crate::tests::test_utils;
-    use regex::Regex;
+    use crate::tests::integration_test_utils::DeltaTest;
 
     #[test]
     fn test_added_file() {
-        let config = integration_test_utils::make_config_from_args(&[]);
-        let output = integration_test_utils::run_delta(ADDED_FILE_INPUT, &config);
-        let output = strip_ansi_codes(&output);
-        assert!(output.contains("\nadded: a.py\n"));
+        DeltaTest::with_args(&[])
+            .with_input(ADDED_FILE_INPUT)
+            .expect_contains("\nadded: a.py\n");
     }
 
     #[test]
     #[ignore] // #128
     fn test_added_empty_file() {
-        let config = integration_test_utils::make_config_from_args(&[]);
-        let output = integration_test_utils::run_delta(ADDED_EMPTY_FILE, &config);
-        let output = strip_ansi_codes(&output);
-        assert!(output.contains("\nadded: file\n"));
+        DeltaTest::with_args(&[])
+            .with_input(ADDED_EMPTY_FILE)
+            .expect_contains("\nadded: file\n");
     }
 
     #[test]
     fn test_added_file_directory_path_containing_space() {
-        let config = integration_test_utils::make_config_from_args(&[]);
-        let output =
-            integration_test_utils::run_delta(ADDED_FILES_DIRECTORY_PATH_CONTAINING_SPACE, &config);
-        let output = strip_ansi_codes(&output);
-        assert!(output.contains("\nadded: with space/file1\n"));
-        assert!(output.contains("\nadded: nospace/file2\n"));
+        DeltaTest::with_args(&[])
+            .with_input(ADDED_FILES_DIRECTORY_PATH_CONTAINING_SPACE)
+            .expect_contains("\nadded: with space/file1\n")
+            .expect_contains("\nadded: nospace/file2\n");
     }
 
     #[test]
     fn test_renamed_file() {
-        let config = integration_test_utils::make_config_from_args(&[]);
-        let output = integration_test_utils::run_delta(RENAMED_FILE_INPUT, &config);
-        let output = strip_ansi_codes(&output);
-        assert!(test_utils::contains_once(
-            &output,
-            "\nrenamed: a.py ⟶   b.py\n"
-        ));
+        DeltaTest::with_args(&[])
+            .with_input(RENAMED_FILE_INPUT)
+            .expect_contains_once("\nrenamed: a.py ⟶   b.py\n");
     }
 
     #[test]
     fn test_copied_file() {
-        let config = integration_test_utils::make_config_from_args(&[]);
-        let output = integration_test_utils::run_delta(GIT_DIFF_WITH_COPIED_FILE, &config);
-        let output = strip_ansi_codes(&output);
-        assert!(test_utils::contains_once(
-            &output,
-            "\ncopied: first_file ⟶   copied_file\n"
-        ));
+        DeltaTest::with_args(&[])
+            .with_input(GIT_DIFF_WITH_COPIED_FILE)
+            .expect_contains_once("\ncopied: first_file ⟶   copied_file\n");
     }
 
     #[test]
     fn test_renamed_file_with_changes() {
-        let config = integration_test_utils::make_config_from_args(&[]);
-        let output = integration_test_utils::run_delta(RENAMED_FILE_WITH_CHANGES_INPUT, &config);
-        let output = strip_ansi_codes(&output);
-        println!("{}", output);
-        assert!(test_utils::contains_once(
-            &output,
-            "\nrenamed: Casks/font-dejavusansmono-nerd-font.rb ⟶   Casks/font-dejavu-sans-mono-nerd-font.rb\n"));
+        let t = DeltaTest::with_args(&[])
+            .with_input(RENAMED_FILE_WITH_CHANGES_INPUT)
+            .expect_contains_once(
+            "\nrenamed: Casks/font-dejavusansmono-nerd-font.rb ⟶   Casks/font-dejavu-sans-mono-nerd-font.rb\n"
+            );
+        println!("{}", t.output);
     }
 
     #[test]
@@ -1587,84 +1573,65 @@ src/align.rs:71: impl<'a> Alignment<'a> { │
 
     #[test]
     fn test_file_mode_change_gain_executable_bit() {
-        let config = integration_test_utils::make_config_from_args(&[]);
-        let output = integration_test_utils::run_delta(
-            GIT_DIFF_FILE_MODE_CHANGE_GAIN_EXECUTABLE_BIT,
-            &config,
-        );
-        let output = strip_ansi_codes(&output);
-        assert!(output.contains(r"src/delta.rs: mode +x"));
+        DeltaTest::with_args(&[])
+            .with_input(GIT_DIFF_FILE_MODE_CHANGE_GAIN_EXECUTABLE_BIT)
+            .expect_contains(r"src/delta.rs: mode +x");
     }
 
     #[test]
     fn test_file_mode_change_lose_executable_bit() {
-        let config = integration_test_utils::make_config_from_args(&[]);
-        let output = integration_test_utils::run_delta(
-            GIT_DIFF_FILE_MODE_CHANGE_LOSE_EXECUTABLE_BIT,
-            &config,
-        );
-        let output = strip_ansi_codes(&output);
-        assert!(output.contains(r"src/delta.rs: mode -x"));
+        DeltaTest::with_args(&[])
+            .with_input(GIT_DIFF_FILE_MODE_CHANGE_LOSE_EXECUTABLE_BIT)
+            .expect_contains(r"src/delta.rs: mode -x");
     }
 
     #[test]
     fn test_file_mode_change_unexpected_bits() {
-        let config =
-            integration_test_utils::make_config_from_args(&["--navigate", "--right-arrow=->"]);
-        let output =
-            integration_test_utils::run_delta(GIT_DIFF_FILE_MODE_CHANGE_UNEXPECTED_BITS, &config);
-        let output = strip_ansi_codes(&output);
-        assert!(output.contains(r"Δ src/delta.rs: 100700 -> 100644"));
+        DeltaTest::with_args(&["--navigate", "--right-arrow=->"])
+            .with_input(GIT_DIFF_FILE_MODE_CHANGE_UNEXPECTED_BITS)
+            .expect_contains(r"Δ src/delta.rs: 100700 -> 100644");
     }
 
     #[test]
     fn test_file_mode_change_with_diff() {
-        let config = integration_test_utils::make_config_from_args(&[
-            "--navigate",
-            "--keep-plus-minus-markers",
-        ]);
-        let output =
-            integration_test_utils::run_delta(GIT_DIFF_FILE_MODE_CHANGE_WITH_DIFF, &config);
-        let output = strip_ansi_codes(&output);
-        let re = Regex::new(r"\n─+\n").unwrap();
-        let output = re.replace(&output, "\n-----\n");
-        assert!(output.contains(
-            "Δ src/script: mode +x
------
-
-─────┐
-• 1: │
-─────┘
--#!/bin/sh
-+#!/bin/bash
-"
-        ));
+        DeltaTest::with_args(&["--navigate", "--keep-plus-minus-markers"])
+            .with_input(GIT_DIFF_FILE_MODE_CHANGE_WITH_DIFF)
+            .expect_contains("Δ src/script: mode +x")
+            .expect_after_skip(
+                5,
+                "
+                ─────┐
+                • 1: │
+                ─────┘
+                -#!/bin/sh
+                +#!/bin/bash",
+            );
     }
 
     #[test]
     fn test_hyperlinks_commit_link_format() {
-        let config = integration_test_utils::make_config_from_args(&[
-            // If commit-style is not set then the commit line is handled in raw
-            // mode, in which case we only format hyperlinks if output is a tty;
-            // this causes the test to fail on Github Actions, but pass locally
-            // if output is left going to the screen.
-            "--commit-style",
-            "blue",
-            "--hyperlinks",
-            "--hyperlinks-commit-link-format",
-            "https://invent.kde.org/utilities/konsole/-/commit/{commit}",
-        ]);
-        let output = integration_test_utils::run_delta(GIT_DIFF_SINGLE_HUNK, &config);
-        assert!(output.contains(r"https://invent.kde.org/utilities/konsole/-/commit/94907c0f136f46dc46ffae2dc92dca9af7eb7c2e"));
+        // If commit-style is not set then the commit line is handled in raw
+        // mode, in which case we only format hyperlinks if output is a tty;
+        // this causes the test to fail on Github Actions, but pass locally
+        // if output is left going to the screen.
+        DeltaTest::with_args(&[
+                "--commit-style",
+                "blue",
+                "--hyperlinks",
+                "--hyperlinks-commit-link-format",
+                "https://invent.kde.org/utilities/konsole/-/commit/{commit}",
+            ])
+            .with_input(GIT_DIFF_SINGLE_HUNK)
+            .expect_raw_contains(
+                r"https://invent.kde.org/utilities/konsole/-/commit/94907c0f136f46dc46ffae2dc92dca9af7eb7c2e"
+                );
     }
 
     #[test]
     fn test_filenames_with_spaces() {
-        let config = integration_test_utils::make_config_from_args(&[]);
-        let output =
-            integration_test_utils::run_delta(GIT_DIFF_NO_INDEX_FILENAMES_WITH_SPACES, &config);
-        let output = strip_ansi_codes(&output);
-        assert!(output.contains("a b ⟶   c d\n"));
+        DeltaTest::with_args(&[])
+            .with_input(GIT_DIFF_NO_INDEX_FILENAMES_WITH_SPACES)
+            .expect_contains("a b ⟶   c d\n");
     }
 
     const GIT_DIFF_SINGLE_HUNK: &str = "\