utils: Add tests for the align_blocks helper in utils.

tests/test_align_snippets.rs

@@ -0,0 +1,74 @@
+extern crate clippy_lints;
+
+use clippy_lints::utils::align_snippets;
+
+#[test]
+fn test_align_snippets_single_line() {
+    assert_eq!("", align_snippets(&[""]));
+    assert_eq!("...", align_snippets(&["..."]));
+}
+
+#[test]
+#[cfg_attr(rustfmt, rustfmt_skip)]
+fn test_align_snippets_multiline() {
+    let expected = "\
+if condition() {
+    do_something();
+    do_another_thing();
+    yet_another_thing();
+    {
+        and_then_an_indented_block();
+    }
+        and_then_something_the_user_indented();"; // expected
+
+    let input = &[
+"\
+if condition() {
+    do_something();",
+"       do_another_thing();",
+"            yet_another_thing();
+            {
+                and_then_an_indented_block();
+            }
+                and_then_something_the_user_indented();",
+    ]; // input
+
+    let got = align_snippets(input);
+    assert_eq!(expected, got);
+
+}
+
+#[test]
+#[cfg_attr(rustfmt, rustfmt_skip)]
+fn test_align_snippets_multiline_with_empty_lines() {
+    let expected = "\
+if condition() {
+    do_something();
+    do_another_thing();
+    yet_another_thing();
+    {
+
+        and_then_an_indented_block();
+    }
+
+        and_then_something_the_user_indented();"; // expected
+
+    let input = &[
+"\
+if condition() {
+    do_something();",
+"       do_another_thing();",
+"            yet_another_thing();
+            {
+
+                and_then_an_indented_block();
+            }
+
+                and_then_something_the_user_indented();",
+    ]; // input
+
+    let got = align_snippets(input);
+    println!("Input: {}\nExpected: {}\nGot: {}", input.join("\n"), &expected, &got);
+    assert_eq!(expected, got);
+}
+