[PATCH olang 2/3] tests: decouple command execution from cli_runner

[Carlos Maniero <carlos@maniero.me>]

This commit separates the logic for executing external programs from the
cli_runner. Previously, the abstraction for handling external programs
was tightly coupled with cli_runner.

However, during integration tests, there are numerous instances where we
need to run an external program. To address this, we introduce a new
function, proc_exec, which is dedicated to managing the execution of
external programs.

Signed-off-by: Carlos Maniero <carlos@maniero.me>
---
 tests/integration/Makefile     |  4 +--
 tests/integration/cli_runner.c | 51 +++++++---------------------
 tests/integration/cli_runner.h | 10 ++++--
 tests/integration/cli_test.c   |  4 +--
 tests/integration/proc_exec.c  | 62 ++++++++++++++++++++++++++++++++++
 tests/integration/proc_exec.h  | 36 ++++++++++++++++++++
 6 files changed, 122 insertions(+), 45 deletions(-)
 create mode 100644 tests/integration/proc_exec.c
 create mode 100644 tests/integration/proc_exec.h

diff --git a/tests/integration/Makefile b/tests/integration/Makefile
index eeebfdd..db2b7d9 100644
--- a/tests/integration/Makefile
+++ b/tests/integration/Makefile
@@ -7,7 +7,7 @@ MUNIT_SRC   := ../shared/munit.c
 MUNIT       := ./munit.o
 
 .PHONY: all
-all: $(MUNIT) cli_runner.o $(TESTS)
+all: $(MUNIT) proc_exec.o cli_runner.o $(TESTS)
 	@for file in $(EXEC_TESTS); do \
                 ./"$$file"; \
         done
@@ -24,7 +24,7 @@ linter: $(SRCS)
 linter-fix: $(SRCS)
 	clang-format -i $?
 
-cli_test: $(MUNIT) cli_runner.o cli_test.o
+cli_test: $(MUNIT) proc_exec.o cli_runner.o cli_test.o
 	$(CC) $? $(CFLAGS) -o $@
 
 $(MUNIT):
diff --git a/tests/integration/cli_runner.c b/tests/integration/cli_runner.c
index 7e4fe9a..5a40e15 100644
--- a/tests/integration/cli_runner.c
+++ b/tests/integration/cli_runner.c
@@ -15,6 +15,7 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 #include "cli_runner.h"
+#include "proc_exec.h"
 #include <assert.h>
 #include <stdbool.h>
 #include <stdio.h>
@@ -62,53 +63,27 @@ create_tmp_file_name(char *file_name)
     close(fd);
 }
 
-cli_result_t
-cli_runner_compiler(char *src, char *args[])
+void
+cli_runner_compiler(cli_result_t* result, char *args[])
 {
     assert_compiler_exists();
 
-    cli_result_t result = { 0 };
-    create_tmp_file_name(result.program_path);
-
-    int fd_link[2];
-
-    if (pipe(fd_link) == -1) {
-        perror("pipe error.");
-        exit(1);
-    }
-
-    pid_t pid = fork();
-
-    if (pid == -1) {
-        perror("fork error.");
-        exit(1);
-    }
-
-    if (pid == 0) {
-        dup2(fd_link[1], STDOUT_FILENO);
-        close(fd_link[0]);
-        close(fd_link[1]);
+    proc_exec_command_t command = {
+        .path = OLANG_COMPILER_PATH,
+        .args = args
+    };
 
-        execv(OLANG_COMPILER_PATH, args);
-        perror("execl error.");
-        exit(127);
-    } else {
-        close(fd_link[1]);
-        if (read(fd_link[0], result.compiler_output, sizeof(result.compiler_output)) == -1) {
-            perror("read error.");
-            exit(1);
-        }
-        int status;
-        waitpid(pid, &status, 0);
-        result.exit_code = WEXITSTATUS(status);
-    }
+    proc_exec(&command);
 
-    return result;
+    result->exec = command.result;
 }
 
 cli_result_t
 cli_runner_compiler_dump_tokens(char *src)
 {
+    cli_result_t result = { 0 };
+
     char *program_args[] = { "0c", "--dump-tokens", src, NULL };
-    return cli_runner_compiler(src, program_args);
+    cli_runner_compiler(&result, program_args);
+    return result;
 }
diff --git a/tests/integration/cli_runner.h b/tests/integration/cli_runner.h
index 7ce4e7b..785cd34 100644
--- a/tests/integration/cli_runner.h
+++ b/tests/integration/cli_runner.h
@@ -16,13 +16,17 @@
  */
 #ifndef CLI_RUNNER_H
 #define CLI_RUNNER_H
+#include "proc_exec.h"
+
 typedef struct cli_result_t
 {
-    int exit_code;
-    char program_path[255];
-    char compiler_output[1024];
+    char binary_path[255];
+    proc_exec_result_t exec;
 } cli_result_t;
 
 cli_result_t
 cli_runner_compiler_dump_tokens(char *src);
+
+cli_result_t
+cli_runner_compiler_compile(char *src);
 #endif
diff --git a/tests/integration/cli_test.c b/tests/integration/cli_test.c
index f7c7417..126f612 100644
--- a/tests/integration/cli_test.c
+++ b/tests/integration/cli_test.c
@@ -22,8 +22,8 @@ static MunitResult
 test_cli_dump_tokens(const MunitParameter params[], void *user_data_or_fixture)
 {
     cli_result_t compilation_result = cli_runner_compiler_dump_tokens("../../examples/main_exit.0");
-    munit_assert_int(compilation_result.exit_code, ==, 0);
-    munit_assert_string_equal(compilation_result.compiler_output,
+    munit_assert_int(compilation_result.exec.exit_code, ==, 0);
+    munit_assert_string_equal(compilation_result.exec.stdout_buf,
                               "../../examples/main_exit.0:1:1: <fn>\n"
                               "../../examples/main_exit.0:1:4: <identifier>\n"
                               "../../examples/main_exit.0:1:8: <(>\n"
diff --git a/tests/integration/proc_exec.c b/tests/integration/proc_exec.c
new file mode 100644
index 0000000..2181ae0
--- /dev/null
+++ b/tests/integration/proc_exec.c
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2024 olang maintainers
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+#include "proc_exec.h"
+#include <assert.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+
+void
+proc_exec(proc_exec_command_t* command)
+{
+    int fd_link[2];
+
+    if (pipe(fd_link) == -1) {
+        perror("pipe error.");
+        exit(1);
+    }
+
+    pid_t pid = fork();
+
+    if (pid == -1) {
+        perror("fork error.");
+        exit(1);
+    }
+
+    if (pid == 0) {
+        dup2(fd_link[1], STDOUT_FILENO);
+        close(fd_link[0]);
+        close(fd_link[1]);
+
+        execv(command->path, command->args);
+        perror("execl error.");
+        exit(127);
+    } else {
+        close(fd_link[1]);
+        if (read(fd_link[0], command->result.stdout_buf, sizeof(command->result.stdout_buf)) == -1) {
+            perror("read error.");
+            exit(1);
+        }
+        int status;
+        waitpid(pid, &status, 0);
+        command->result.exit_code = WEXITSTATUS(status);
+    }
+}
diff --git a/tests/integration/proc_exec.h b/tests/integration/proc_exec.h
new file mode 100644
index 0000000..135aa6a
--- /dev/null
+++ b/tests/integration/proc_exec.h
@@ -0,0 +1,36 @@
+/*
+ * Copyright (C) 2024 olang maintainers
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+#ifndef PROC_EXEC_H
+#define PROC_EXEC_H
+#include <stdlib.h>
+
+typedef struct proc_exec_result
+{
+    int exit_code;
+    char stdout_buf[1024];
+} proc_exec_result_t;
+
+typedef struct proc_exec_command
+{
+    char* path;
+    char** args;
+    proc_exec_result_t result;
+} proc_exec_command_t;
+
+void
+proc_exec(proc_exec_command_t* command);
+#endif
-- 
2.34.1