Add import parsing

Co-authored-by: Copilot <copilot@github.com>

v0/ast.h

@@ -4,6 +4,13 @@
 #ifndef AST_H
 #define AST_H
 
+#include <stddef.h>
+
+typedef struct {
+	/// @brief The name of the module being imported.
+	char* module_name;
+} ImportDeclaration;
+
 /**
  * The top-level model.
  * Every file matches an entire Module.
@@ -11,6 +18,12 @@
 typedef struct {
 	/// @brief The name of the module.
 	char* name;
+
+	/// @brief The list of imports in the module.
+	ImportDeclaration* imports;
+	
+	/// @brief The number of imports in the module.
+	size_t import_count;
 } Module;
 
 #endif

v0/parser.c

@@ -32,11 +32,55 @@ Module* parser_parse(TokenStream* ts) {
 		return NULL;
 	}
 
+	module->imports = NULL;
+	module->import_count = 0;
+
+	while (1) {
+		t = tokenstream_next(ts);
+		if (t.token != TOKEN_IMPORT) {
+			break;
+		}
+
+		ImportDeclaration* new_imports = realloc(module->imports, (module->import_count + 1) * sizeof(ImportDeclaration));
+		if (!new_imports) {
+			parser_free(module);
+			return NULL;
+		}
+		module->imports = new_imports;
+
+		t = tokenstream_next(ts);
+		if (t.token != TOKEN_IDENTIFIER) {
+			parser_free(module);
+			return NULL;
+		}
+
+		module->imports[module->import_count].module_name = (char*)malloc(t.text.length + 1);
+		if (!module->imports[module->import_count].module_name) {
+			parser_free(module);
+			return NULL;
+		}
+		memcpy(module->imports[module->import_count].module_name, t.text.data, t.text.length);
+		module->imports[module->import_count].module_name[t.text.length] = '\0';
+		module->import_count++;
+
+		t = tokenstream_next(ts);
+		if (t.token != TOKEN_SEMICOLON) {
+			parser_free(module);
+			return NULL;
+		}
+	}
+
 	return module;
 }
 
 void parser_free(Module* module) {
 	if (module == NULL) return;
+	if (module->imports != NULL) {
+		for (size_t i = 0; i < module->import_count; i++) {
+			free(module->imports[i].module_name);
+		}
+		free(module->imports);
+	}
 	free(module->name);
 	free(module);
 }

v0/test.c

@@ -67,6 +67,14 @@ void assert_log_file(const char* filepath, const char* msg) {
     free(content);
 }
 
+void assert_int(int expected, int actual, const char* msg) {
+    if (expected != actual) {
+        char buf[64];
+        snprintf(buf, sizeof(buf), "%s (expected %d, got %d)", msg, expected, actual);
+        fail(buf);
+    }
+}
+
 static void log_append(const char* msg) {
     size_t oldLen = s_logOutput ? strlen(s_logOutput) : 0;
     size_t newLen = oldLen + strlen(msg) + 1;
@@ -111,6 +119,7 @@ static TestCase s_tests[] = {
     {"tokenstream_unknown_token", test_tokenstream_unknown_token},
     {"tokenstream_info", test_tokenstream_info},
     {"parser_module_name", test_parser_module_name},
+    {"parser_imports", test_parser_imports},
     {"log_error", test_log_error},
     {"log_on_line", test_log_on_line},
 };

v0/test.h

@@ -44,4 +44,9 @@ void assert_log(const char* expected, const char* msg);
  */
 void assert_log_file(const char* filepath, const char* msg);
 
+/**
+ * Asserts that two integers are equal.
+ */
+void assert_int(int expected, int actual, const char* msg);
+
 #endif

v0/test_parser.c

@@ -12,3 +12,28 @@ static void test_parser_module_name(void) {
 	parser_free(m);
 	tokenstream_close(ts);
 }
+
+static void test_parser_bad_module_name(void) {
+	TokenStream* ts = tokenstream_open("test.c", "import other_module;");
+	Module* m = parser_parse(ts);
+
+	assert_log_file("bad_module_name.log", "expected error to be logged for bad module name");
+
+	parser_free(m);
+	tokenstream_close(ts);
+}
+
+static void test_parser_imports(void) {
+	TokenStream* ts = tokenstream_open("test.c", "module my_module; import other_module;");
+	Module* m = parser_parse(ts);
+
+	assert_not_null(m, "expected module to be parsed");
+	assert_str("my_module", m->name, "expected name 'my_module'");
+	
+	assert_not_null(m->imports, "expected imports to be parsed");
+	assert_int(1, m->import_count, "expected one import");
+	assert_str("other_module", m->imports[0].module_name, "expected import name 'other_module'");
+
+	parser_free(m);
+	tokenstream_close(ts);
+}

v0/tests/bad_module_log.txt

@@ -0,0 +1,4 @@
+--- test.c ---
+1| import other_module.c
+   ^^^^^^
+   expected `module`