Treat Makefile text as atoms

Improves another case identified in #476

CHANGELOG.md

@@ -1,5 +1,9 @@
 ## 0.45 (unreleased)
 
+### Parsing
+
+Improved parsing for Makefiles.
+
 ## 0.44 (released 2nd March 2023)
 
 ### Parsing

sample_files/cli_tests/makefile_after.mk

@@ -0,0 +1 @@
+CCFLAGS+=-std=c99 -D_DEFAULT_SOURCE -DVERSION=\"$(VERS)\" -O2 -D_FORTIFY_SOURCE=2 -fstack-protector-all $(CFLAGS) -g

sample_files/cli_tests/makefile_before.mk

@@ -0,0 +1 @@
+CCFLAGS+=-std=c99 -D_DEFAULT_SOURCE -DVERSION=\"$(VERS)\" -O2 -Wall -Werror -D_FORTIFY_SOURCE=2 -fstack-protector-all $(CFLAGS) -g

src/parse/tree_sitter_parser.rs

@@ -608,7 +608,7 @@ pub fn from_language(language: guess::Language) -> TreeSitterConfig {
             let language = unsafe { tree_sitter_make() };
             TreeSitterConfig {
                 language,
-                atom_nodes: vec!["shell_text"].into_iter().collect(),
+                atom_nodes: vec!["shell_text", "text"].into_iter().collect(),
                 delimiter_tokens: vec![("(", ")")].into_iter().collect(),
                 highlight_query: ts::Query::new(
                     language,

tests/cli.rs

@@ -55,3 +55,16 @@ fn check_only_text_file() {
     let predicate_fn = predicate::str::contains("Has changes");
     cmd.assert().stdout(predicate_fn);
 }
+
+#[test]
+fn makefile_text_as_atom() {
+    use predicates::prelude::*;
+
+    let mut cmd = Command::cargo_bin("difft").unwrap();
+
+    cmd.arg("sample_files/cli_tests/makefile_before.mk")
+        .arg("sample_files/cli_tests/makefile_after.mk");
+
+    let predicate_fn = predicate::str::contains("CCFLAGS");
+    cmd.assert().stdout(predicate_fn);
+}