cli: Add AST pretty-printing option (--ast-dump)

Parsing can be a complex process, and it's not always easy to get a
clear picture of what's happening with the AST.  This commit adds a new
feature to the CLI that allows us to pretty-print the AST (outputs to
stdout), making it easier to visualize the tree structure and understand
how the parser is working.

The new --ast-dump option generates a human-readable representation of
the AST, including node types, values, and child relationships. This
information can be invaluable for debugging and understanding the
parser's behavior.

Signed-off-by: Johnny Richard <johnny@johnnyrichard.com>
Reviewed-by: Carlos Maniero <carlos@maniero.me>

1 files changed, 28 insertions, 2 deletions

diff --git a/src/main.c b/src/main.c
index e3caec1..4f68256 100644
--- a/src/main.c
+++ b/src/main.c
@@ -19,6 +19,7 @@
 #include <string.h>
 
 #include "ast.h"
+#include "ast_pretty_printer.h"
 #include "gas_assembly_generator.h"
 #include "lexer.h"
 #include "parser.h"
@@ -34,6 +35,14 @@ generate_gas_x86_64_linux(ast_node_t *func)
 }
 
 static void
+pretty_print_ast(ast_node_t *ast)
+{
+  ast_pretty_printer_t printer;
+  ast_pretty_printer_init(&printer, stdout);
+  ast_pretty_printer_print_ast(&printer, ast);
+}
+
+static void
 print_usage(void)
 {
   fputs("pipac <filename.pipa>\n", stderr);
@@ -58,7 +67,20 @@ main(int argc, char **argv)
     return EXIT_FAILURE;
   }
 
-  char *filepath = argv[1];
+  char *filepath;
+  bool should_dump_ast = false;
+
+  // TODO: Handle command line arguments properly
+  if (argc < 3) {
+    filepath = argv[1];
+  } else {
+    if (strcmp(argv[1], "--ast-dump") != 0) {
+      print_usage();
+      return EXIT_FAILURE;
+    }
+    should_dump_ast = true;
+    filepath = argv[2];
+  }
 
   lexer_t lexer;
   lexer_init(&lexer, filepath);
@@ -74,7 +96,11 @@ main(int argc, char **argv)
     return EXIT_FAILURE;
   }
 
-  generate_gas_x86_64_linux(func);
+  if (should_dump_ast) {
+    pretty_print_ast(func);
+  } else {
+    generate_gas_x86_64_linux(func);
+  }
 
   scope_destroy(scope);
   ast_node_destroy(func);