fix/refactor: Modified evaluate and changed it to evaluate_tree

So i did what the last commit said, also fixed parse_expr because it was
still using malloc for allocating new nodes so i made it use arena_alloc
like it should, did the very first tests so it's all good, i think is
readdy to merge.

CMakeLists.txt

@@ -3,6 +3,14 @@ project(calculator VERSION 1.0 LANGUAGES C)
 
 set(CMAKE_C_STANDARD 11)
 set(CMAKE_C_STANDARD_REQUIRED ON)
+include(FetchContent)
+
+FetchContent_Declare(
+    arena
+    GIT_REPOSITORY https://laentropia-homelab.tail7368da.ts.net/laentropia/Arena.git
+    GIT_TAG main
+    SOURCE_DIR ${CMAKE_SOURCE_DIR}/external/arena
+)
 
 # Export compile_commands.json (para clangd)
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
@@ -14,13 +22,29 @@ add_compile_options(
 )
 
 
-include_directories(include)
+FetchContent_MakeAvailable(arena)
+
+add_library(arena STATIC
+    external/arena/src/arena.c
+)
+
+target_include_directories(arena
+    PUBLIC ${CMAKE_SOURCE_DIR}/external/arena/include
+)
 
 add_library(calculator_lib
     src/lexer.c
     src/parser.c
-    src/ast.c
     src/evaluator.c
+    src/ASTNodeArray.c
+)
+
+target_include_directories(calculator_lib
+    PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/include
+)
+
+target_link_libraries(calculator_lib
+    PUBLIC arena
 )
 
 add_executable(calculator src/main.c)

include/evaluator.h

@@ -0,0 +1,11 @@
+#ifndef EVALUATOR_H
+#define EVALUATOR_H
+
+#include "lexer.h"
+#include "parser.h"
+#include <stdint.h>
+
+int64_t evaluate(ParseResult context);
+int64_t evaluate_tree(ASTNode *tree);
+
+#endif // !EVALUATOR_H

include/lexer.h

@@ -59,7 +59,6 @@ typedef struct {
     ASTNode *data;
 } ASTNodeArray;
 
-// Basic array functionality
 ASTNodeArray ASTNodeArray_init(size_t size);
 void ASTNodeArray_free(ASTNodeArray *arr);
 ASTNodeArrayErr ASTNodeArray_push(ASTNodeArray *arr, ASTNode node);
@@ -74,5 +73,6 @@ LexerErr tokenize_number(const char* input, size_t *offset, ASTNode *out);
 LexerErr string_to_integer(const char buf[], int64_t *number);
 bool isoperator(int c);
 Operator char_to_operator(int c);
+char operator_to_char(Operator op);
 
 #endif // !LEXER_H

include/parser.h

@@ -1,14 +1,35 @@
+#ifndef PARSER_H
+#define PARSER_H
+
 #include "lexer.h"
+#include "arena.h"
+#include <stdint.h>
 
 typedef struct {
     ASTNode *head;
 } AST;
 
-typedef enum {
+typedef struct {
-    PARSER_NUD, // Null Denotation
+    ASTNodeArray *arr;
-    PARSER_LED, // Left Denotation
+    size_t pos;
-} ParserState;
+} ASTNodeSlice;
 
-size_t node_lbp(Operator op);
+typedef struct {
-size_t node_rbp(Operator op);
+    Arena arena;
-AST parse(ASTNodeArray arr);
+    ASTNode *tree;
+} ParseResult;
+
+ASTNode ASTNodeSlice_peek(ASTNodeSlice *slice);
+ASTNode ASTNodeSlice_next(ASTNodeSlice *slice);
+bool ASTNodeSlice_is_valid(ASTNodeSlice *slice);
+
+ASTNode *nud(ASTNodeSlice *slice);
+ASTNode *led(ASTNodeSlice *slice, size_t right_precedence);
+
+uint8_t node_lbp(ASTNode node);
+uint8_t node_rbp(ASTNode node);
+
+ParseResult parse(ASTNodeArray *arr);
+ASTNode *parse_expr(ASTNodeSlice *slice, Arena *arena, uint8_t min_bp);
+
+#endif // !PARSER_H

src/ASTNodeArray.c

@@ -0,0 +1,108 @@
+#include "lexer.h"
+#include <stdlib.h>
+
+#define NODE_ARRAY_DEFAULT_SIZE 64
+// Helps  state machine for the lexer :)
+typedef enum {
+    WAIT_FOR_NUMBER,
+    WAIT_FOR_OPERATOR,
+} LexerState;
+
+ASTNodeArray ASTNodeArray_init(size_t size) {
+    ASTNodeArray new;
+    new.len = 0;      // if 0 then use default
+    new.cap = size == 0 ? NODE_ARRAY_DEFAULT_SIZE : size;
+    new.data = malloc(new.cap * sizeof(ASTNode));
+    return new;
+}
+
+void ASTNodeArray_free(ASTNodeArray *arr) {
+    free(arr->data);
+    arr->cap = 0;
+    arr->len = 0;
+}
+
+ASTNodeArrayErr ASTNodeArray_get(const ASTNodeArray *arr, size_t index, ASTNode *out) {
+    if (arr == NULL) {
+        return ARRAY_NULL;
+    }
+
+    if (out == NULL) {
+        return ARRAY_NULL_ARG;
+    }
+
+    if (arr->len == 0) {
+        return ARRAY_EMPTY;
+    }
+
+    if (index >= arr->len) {
+        return ARRAY_OUT_OF_BOUNDS;
+    }
+
+    *out = arr->data[index];
+
+    return ARRAY_OK;
+}
+
+ASTNodeArrayErr ASTNodeArray_push(ASTNodeArray *arr, ASTNode node) {
+    if (arr == NULL) {
+        return ARRAY_NULL;
+    }
+
+    if (arr->len >= arr->cap) {
+        size_t new_cap = arr->cap * 2;
+        ASTNode *tmp = realloc(arr->data, new_cap * sizeof(ASTNode));
+        if (tmp == NULL) {
+            return ARRAY_ALLOC;
+        }
+        arr->data = tmp;
+        arr->cap = new_cap;
+    }
+
+    arr->data[arr->len] = node;
+    arr->len = arr->len + 1;
+
+    return ARRAY_OK;
+}
+
+ASTNodeArrayErr ASTNodeArray_pop(ASTNodeArray *arr, size_t index, ASTNode *out) {
+    if (arr == NULL) {
+        return ARRAY_NULL;
+    }
+
+    if (arr->len == 0) {
+        return ARRAY_EMPTY;
+    }
+
+    if (index >= arr->len) {
+        return ARRAY_OUT_OF_BOUNDS;
+    }
+
+    if (arr->cap / 4 > arr->len) {
+        size_t new_cap = arr->cap / 2;
+        ASTNode *tmp = realloc(arr->data, new_cap * sizeof(ASTNode));
+        if (tmp == NULL) {
+            return ARRAY_ALLOC;
+        }
+        arr->data = tmp;
+        arr->cap = new_cap;
+    }
+    
+    if (out != NULL) {
+        ASTNode node_to_delete = arr->data[index];
+        *out = node_to_delete;
+    }
+
+    for (size_t i = index; i < arr->len - 1; i++) {
+        arr->data[index] = arr->data[index + 1];
+    }
+
+    return ARRAY_OK;
+}
+
+size_t ASTNodeArray_len(ASTNodeArray *arr) {
+    if (arr == NULL) {
+        return 0;
+    }
+    return arr->len;
+}

src/evaluator.c

@@ -0,0 +1,36 @@
+#include "evaluator.h"
+#include "arena.h"
+#include "lexer.h"
+#include "parser.h"
+#include <stdint.h>
+
+
+int64_t evaluate_tree(ASTNode *tree) {
+    if (tree->type == NODE_BINARY_OP) {
+        Operator op = tree->data.binary.op;
+        ASTNode *left = tree->data.binary.left;
+        ASTNode *right = tree->data.binary.right;
+        
+        switch (op) {
+            case OP_ADD:
+                return evaluate_tree(left) + evaluate_tree(right);
+            case OP_SUB:
+                return evaluate_tree(left) - evaluate_tree(right);
+            case OP_MUL:
+                return evaluate_tree(left) * evaluate_tree(right);
+            case OP_DIV:
+                return evaluate_tree(left) / evaluate_tree(right);
+
+        }
+    }
+
+    int64_t return_val = tree->data.integer;
+    return return_val;
+}
+
+int64_t evaluate(ParseResult context) {
+    int64_t result = evaluate_tree(context.tree);
+    arena_destroy(&context.arena);
+
+    return result;
+}

src/lexer.c

@@ -6,111 +6,11 @@
 #include <strings.h>
 #include <limits.h>
 
-#define NODE_ARRAY_DEFAULT_SIZE 64
-// Helps  state machine for the lexer :)
 typedef enum {
     WAIT_FOR_NUMBER,
-    WAIT_FOR_OPERATOR,
+    WAIT_FOR_OPERATOR
 } LexerState;
 
-ASTNodeArray ASTNodeArray_init(size_t size) {
-    ASTNodeArray new;
-    new.len = 0;      // if 0 then use default
-    new.cap = size == 0 ? NODE_ARRAY_DEFAULT_SIZE : size;
-    new.data = malloc(new.cap * sizeof(ASTNode));
-    return new;
-}
-
-void ASTNodeArray_free(ASTNodeArray *arr) {
-    free(arr->data);
-    arr->cap = 0;
-    arr->len = 0;
-}
-
-ASTNodeArrayErr ASTNodeArray_get(const ASTNodeArray *arr, size_t index, ASTNode *out) {
-    if (arr == NULL) {
-        return ARRAY_NULL;
-    }
-
-    if (out == NULL) {
-        return ARRAY_NULL_ARG;
-    }
-
-    if (arr->len == 0) {
-        return ARRAY_EMPTY;
-    }
-
-    if (index >= arr->len) {
-        return ARRAY_OUT_OF_BOUNDS;
-    }
-
-    *out = arr->data[index];
-
-    return ARRAY_OK;
-}
-
-ASTNodeArrayErr ASTNodeArray_push(ASTNodeArray *arr, ASTNode node) {
-    if (arr == NULL) {
-        return ARRAY_NULL;
-    }
-
-    if (arr->len >= arr->cap) {
-        size_t new_cap = arr->cap * 2;
-        ASTNode *tmp = realloc(arr->data, new_cap * sizeof(ASTNode));
-        if (tmp == NULL) {
-            return ARRAY_ALLOC;
-        }
-        arr->data = tmp;
-        arr->cap = new_cap;
-    }
-
-    arr->data[arr->len] = node;
-    arr->len = arr->len + 1;
-
-    return ARRAY_OK;
-}
-
-ASTNodeArrayErr ASTNodeArray_pop(ASTNodeArray *arr, size_t index, ASTNode *out) {
-    if (arr == NULL) {
-        return ARRAY_NULL;
-    }
-
-    if (arr->len == 0) {
-        return ARRAY_EMPTY;
-    }
-
-    if (index >= arr->len) {
-        return ARRAY_OUT_OF_BOUNDS;
-    }
-
-    if (arr->cap / 4 > arr->len) {
-        size_t new_cap = arr->cap / 2;
-        ASTNode *tmp = realloc(arr->data, new_cap * sizeof(ASTNode));
-        if (tmp == NULL) {
-            return ARRAY_ALLOC;
-        }
-        arr->data = tmp;
-        arr->cap = new_cap;
-    }
-    
-    if (out != NULL) {
-        ASTNode node_to_delete = arr->data[index];
-        *out = node_to_delete;
-    }
-
-    for (size_t i = index; i < arr->len - 1; i++) {
-        arr->data[index] = arr->data[index + 1];
-    }
-
-    return ARRAY_OK;
-}
-
-size_t ASTNodeArray_len(ASTNodeArray *arr) {
-    if (arr == NULL) {
-        return 0;
-    }
-    return arr->len;
-}
 
 LexerErr tokenize(const char *input, ASTNodeArray *out) {
     size_t offset = 0;
@@ -248,3 +148,16 @@ Operator char_to_operator(int c) {
             return -1;
     }
 }
+
+char operator_to_char(Operator op) {
+    switch (op) {
+        case OP_ADD:
+            return '+';
+        case OP_SUB:
+            return '-';
+        case OP_MUL:
+            return '*';
+        case OP_DIV:
+            return '/';
+    }
+}

src/main.c

@@ -1,7 +1,31 @@
+#include "arena.h"
+#include "evaluator.h"
+#include "lexer.h"
+#include "parser.h"
+#include <stdint.h>
+#include <inttypes.h>
 #include <stdlib.h>
 #include <stdio.h>
 
-int main(int argc, char *argv[]) {
+int main(void) {
-    puts("Hello");
+    char buf[256];
+    printf("Insert a valid mathematical expression: ");
+    
+    int c;
+    int pos = 0;
+    while ((c = getc(stdin)) != '\n' && c != EOF) {
+        buf[pos] = c;
+        pos++;
+    }
+    buf[pos] = '\0';
+
+    ASTNodeArray context;
+    tokenize(buf, &context);
+
+    ParseResult par = parse(&context);
+    int64_t result = evaluate(par);
+
+
+    printf("El resultado es: %" PRIi64 "\n", result);
     return EXIT_SUCCESS;
 }

src/parser.c

@@ -1,9 +1,18 @@
 #include "parser.h"
 #include "lexer.h"
+#include "arena.h"
+#include <stdalign.h>
+#include <stdbool.h>
+#include <stdint.h>
 #include <stdlib.h>
 
-size_t node_lbp(Operator op) {
+
-    switch (op) {
+uint8_t node_lbp(ASTNode node) {
+    if (node.type == NODE_INTEGER) {
+        return 0;
+    }
+
+    switch (node.data.binary.op) {
         case OP_ADD:
         case OP_SUB:
             return 10;
@@ -11,17 +20,115 @@ size_t node_lbp(Operator op) {
         case OP_DIV:
         case OP_MUL:
             return 20;
+        default:
+            return 0;
     }
 }
 
-size_t node_rbp(Operator op) {
+uint8_t node_rbp(ASTNode node) {
-    switch (op) {
+    if (node.type == NODE_INTEGER) {
+        return 0;
+    }
+
+    switch (node.data.binary.op) {
         case OP_ADD:
         case OP_SUB:
-            return 10;
+            return 11;
             break;
         case OP_DIV:
         case OP_MUL:
-            return 20;
+            return 21;
+        default:
+            return 0;
     }
 }
+
+ASTNode ASTNodeSlice_next(ASTNodeSlice *slice) {
+    return slice->arr->data[slice->pos++];
+}
+
+ASTNode ASTNodeSlice_peek(ASTNodeSlice *slice) {
+    return slice->arr->data[slice->pos];
+}
+
+bool ASTNodeSlice_is_valid(ASTNodeSlice *slice) {
+    if (slice->arr->len < 1) {
+        return false;
+    }
+    if (slice->pos >= slice->arr->len) {
+        return false;
+    }
+
+    return true;
+}
+
+ParseResult parse(ASTNodeArray *arr) {
+    ASTNodeSlice context = {
+        .arr = arr,
+        .pos = 0,
+    };
+    Arena arena = arena_init(sizeof(ASTNode) * arr->len).arena;
+
+    return (ParseResult) {
+        .arena = arena,
+        .tree = parse_expr(&context, &arena, 0)};
+}
+
+ASTNode *parse_expr(ASTNodeSlice *slice, Arena *arena, uint8_t min_bp) {
+    arena_ensure_capacity(
+        arena,
+        sizeof(ASTNode),
+        alignof(ASTNode)
+    );
+
+    ASTNode *left_side = arena_unwrap_pointer(
+        arena_alloc(
+            arena,
+            sizeof(ASTNode),
+            alignof(ASTNode)
+        )
+    );
+
+    *left_side = ASTNodeSlice_next(slice);
+
+    while (true) {
+        if (!ASTNodeSlice_is_valid(slice)) {
+            break;
+        }
+
+        ASTNode operator = ASTNodeSlice_peek(slice);
+        uint8_t rbp = node_rbp(operator);
+        uint8_t lbp = node_lbp(operator);
+
+        if (lbp < min_bp) {
+            break;
+        }
+
+        ASTNodeSlice_next(slice);
+        ASTNode *right_side = parse_expr(slice, arena, rbp);
+
+        arena_ensure_capacity(
+            arena,
+            sizeof(ASTNode),
+            alignof(ASTNode));
+        ASTNode *new_node = arena_unwrap_pointer(
+            arena_alloc(
+                arena, 
+                sizeof(ASTNode), 
+                alignof(ASTNode)
+            )
+        );
+        *new_node = operator;
+
+        new_node->data.binary.left = left_side;
+        new_node->data.binary.right = right_side;
+
+        left_side = new_node;
+    }
+
+
+    return left_side;
+}
+
+
+

test/CMakeLists.txt

@@ -2,6 +2,8 @@ find_package(cmocka REQUIRED)
 
 add_executable(test_nodeArray test_ASTNodeArray.c)
 add_executable(test_lexer test_lexer.c)
+add_executable(test_parser test_parser.c)
+add_executable(test_evaluator test_evaluator.c)
 
 target_link_libraries(test_nodeArray
     calculator_lib
@@ -13,5 +15,17 @@ target_link_libraries(test_lexer
     cmocka::cmocka
 )
 
+target_link_libraries(test_parser
+    calculator_lib
+    cmocka::cmocka
+)
+
+target_link_libraries(test_evaluator
+    calculator_lib
+    cmocka::cmocka
+)
+
 add_test(NAME nodeArray_tests COMMAND test_nodeArray)
 add_test(NAME lexer_tests COMMAND test_lexer)
+add_test(NAME parser_tests COMMAND test_parser)
+add_test(NAME evaluator_tests COMMAND test_evaluator)

test/test_evaluator.c

@@ -0,0 +1,32 @@
+#include "lexer.h"
+#include "parser.h"
+#include "evaluator.h"
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <setjmp.h>
+#include <cmocka.h>
+#include <stdlib.h>
+
+static void test_basic_evaluation(void** state) {
+    (void) state;
+
+    char expr[256] = "2 + 4 * 40 / 2";
+    ASTNodeArray context;
+
+    tokenize(expr, &context);
+    ParseResult result = parse(&context);
+    int64_t value = evaluate(result);
+
+    assert_int_equal(value, 82);
+}
+
+int main(void) {
+    const struct CMUnitTest tests[] = {
+        cmocka_unit_test(test_basic_evaluation),
+    };
+
+    cmocka_run_group_tests(tests, NULL, NULL);
+    return EXIT_SUCCESS;
+}

test/test_parser.c

@@ -1,5 +1,81 @@
-#include <stdlib.h>
+#include "arena.h"
+#include "lexer.h"
+#include "parser.h"
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <setjmp.h>
+#include <cmocka.h>
 
-int main() {
+static void test_parsing_basic_expression(void **state) {
-    return EXIT_SUCCESS;
+    (void) state;
+
+    char expr[256] = "2 + 3 / 66 * 789";
+    ASTNodeArray tokens;
+    ASTNode node;
+    
+    assert_int_equal(tokenize(expr, &tokens), LEXER_OK);
+    assert_int_equal(tokens.len, 7);
+
+    ParseResult result = parse(&tokens);
+    // Assert head is +
+    assert_int_equal(result.tree->type, NODE_BINARY_OP);
+    assert_int_equal(result.tree->data.binary.op, OP_ADD);
+
+    assert_int_equal(result.tree->data.binary.left->type, NODE_INTEGER);
+    assert_int_equal(result.tree->data.binary.left->data.integer, 2);
+
+
+    assert_int_equal(
+            result.tree->data.binary.right->type,
+            NODE_BINARY_OP
+            );
+    assert_int_equal(
+            result.tree->data.binary.right->data.binary.op, 
+            OP_MUL
+            );
+
+    assert_int_equal(
+            result.tree->data.binary.right->data.binary.right->type,
+            NODE_INTEGER);
+    assert_int_equal(
+            result.tree->data.binary.right->data.binary.right->data.integer,
+            789);
+
+    assert_int_equal(
+            result.tree->data.binary.right->data.binary.left->type, 
+            NODE_BINARY_OP
+            );
+    assert_int_equal(
+            result.tree->data.binary.right->data.binary.left->data.binary.op, 
+            OP_DIV
+            );
+
+    assert_int_equal(
+            result.tree->data.binary.right->data.binary.left->data.binary.right->type, 
+            NODE_INTEGER
+            );
+    assert_int_equal(
+            result.tree->data.binary.right->data.binary.left->data.binary.right->data.integer, 
+            66
+            );
+
+    assert_int_equal(
+            result.tree->data.binary.right->data.binary.left->data.binary.left->type, 
+            NODE_INTEGER
+            );
+    assert_int_equal(
+            result.tree->data.binary.right->data.binary.left->data.binary.left->data.integer, 
+            3
+            );
+    arena_destroy(&result.arena);
+}
+
+int main(void) {
+    const struct CMUnitTest tests [] = {
+        cmocka_unit_test(test_parsing_basic_expression),
+    };
+
+    return cmocka_run_group_tests(tests, NULL, NULL);
 }