Enhance build process: improve source file handling, ensure output directories exist, and merge global flags into shared libs and tools

builder/builder.v

@@ -215,9 +215,12 @@ fn build_from_directives(mut build_config config.BuildConfig, mut shared_libs_bu
             if os.is_file(source_file) {
                 break
             }
+            // if none matched, reset to empty for next iteration
+            source_file = ''
         }
 
-        if source_file == '' {
+        // Ensure the found source actually exists; avoid using last attempted extension if none matched
+        if source_file == '' || !os.is_file(source_file) {
             if build_config.verbose {
                 println('Warning: Source file not found for unit ${unit_name}')
             }
@@ -255,6 +258,8 @@ fn build_from_directives(mut build_config config.BuildConfig, mut shared_libs_bu
         if directive.is_shared {
             // Link shared library
             lib_output := os.join_path(build_config.bin_dir, 'lib', directive.unit_name)
+            // ensure output directory exists
+            os.mkdir_all(lib_output) or { return error('Failed to create shared lib output directory: ${lib_output}') }
             println('Linking shared library: ${lib_output}')
             link_shared_library([obj_file], directive.unit_name, lib_output, build_config, config.SharedLibConfig{
                 name: directive.unit_name
@@ -457,6 +462,11 @@ fn build_shared_library(mut lib_config config.SharedLibConfig, build_config conf
         if needs_recompile(src_file, obj_file) {
             println('Compiling ${lib_config.name}: ${src_file}...')
             lib_target_config := config.TargetConfig(lib_config)
+            // show compile command if verbose
+            if lib_config.verbose || build_config.verbose {
+                cmd_preview := config.build_shared_compiler_command(src_file, obj_file, build_config, lib_target_config)
+                println('Compile command (preview): ${cmd_preview}')
+            }
             compile_tasks << CompileTask{source: src_file, obj: obj_file, target_config: lib_target_config}
         } else {
             if lib_config.verbose {
@@ -478,6 +488,8 @@ fn build_shared_library(mut lib_config config.SharedLibConfig, build_config conf
     
     // Link shared library
     lib_output := os.join_path(lib_config.output_dir, lib_config.name)
+    // ensure output directory exists
+    os.mkdir_all(lib_config.output_dir) or { return error('Failed to create shared lib output directory: ${lib_config.output_dir}') }
     println('Linking shared library: ${lib_output}')
     link_shared_library(object_files, lib_config.name, lib_output, build_config, lib_config) or { 
         return error('Failed to link shared library ${lib_config.name}')
@@ -522,6 +534,11 @@ fn build_tool(mut tool_config config.ToolConfig, build_config config.BuildConfig
         if needs_recompile(src_file, obj_file) {
             println('Compiling ${tool_config.name}: ${src_file}...')
             tool_target_config := config.TargetConfig(tool_config)
+            // show compile command if verbose
+            if tool_config.verbose || build_config.verbose {
+                cmd_preview := config.build_shared_compiler_command(src_file, obj_file, build_config, tool_target_config)
+                println('Compile command (preview): ${cmd_preview}')
+            }
             compile_tasks << CompileTask{source: src_file, obj: obj_file, target_config: tool_target_config}
         } else {
             if tool_config.verbose {
@@ -576,6 +593,7 @@ fn compile_file(source_file string, object_file string, build_config config.Buil
         println('Compile command: ${cmd}')
     }
 
+    // Execute compile
     res := os.execute(cmd)
     if res.exit_code != 0 {
         return error('Compilation failed with exit code ${res.exit_code}:\n${res.output}')
@@ -766,6 +784,11 @@ fn find_source_files(dir string) ![]string {
 }
 
 fn needs_recompile(source_file string, object_file string) bool {
+    if !os.is_file(source_file) {
+        // source missing, signal recompile to allow upstream code to handle error
+        return true
+    }
+
     src_mtime := os.file_last_mod_unix(source_file)
     obj_mtime := if os.is_file(object_file) {
         os.file_last_mod_unix(object_file)

config/config.v

@@ -89,7 +89,7 @@ __global:
 
 // default config
 pub const default_config = BuildConfig{
-    project_name: 'project'
+    project_name: ''
     src_dir: 'src'
     build_dir: 'build'
     bin_dir: 'bin'
@@ -135,7 +135,8 @@ pub fn (mut build_config BuildConfig) parse_build_directives() ! {
                 continue
             }
             
-            parts := line[17..].trim_space().split('(')
+            // slice after the prefix '// build-directive:' (19 characters)
+            parts := line[19..].trim_space().split('(')
             if parts.len != 2 {
                 continue
             }
@@ -292,10 +293,10 @@ pub fn parse_args() !BuildConfig {
             else {
                 if !arg.starts_with('-') {
                     // Treat as project name or first source file
-                    if build_config.project_name == 'project' {
+                    if build_config.project_name == '' {
                         build_config.project_name = arg
                     } else {
-                        // Add as default tool
+                        // Add as default tool using the project name
                         mut default_tool := ToolConfig{
                             name: build_config.project_name
                             sources: [arg]
@@ -554,6 +555,61 @@ pub fn parse_config_file(filename string) !BuildConfig {
         if !tool.verbose { tool.verbose = build_config.verbose }
     }
 
+    // Merge global flags and includes into individual shared libs and tools
+    for mut lib in build_config.shared_libs {
+        // merge include dirs
+        for inc in build_config.include_dirs {
+            if inc != '' && inc !in lib.include_dirs {
+                lib.include_dirs << inc
+            }
+        }
+        // merge cflags
+        for flag in build_config.cflags {
+            if flag != '' && flag !in lib.cflags {
+                lib.cflags << flag
+            }
+        }
+        // merge ldflags
+        for flag in build_config.ldflags {
+            if flag != '' && flag !in lib.ldflags {
+                lib.ldflags << flag
+            }
+        }
+        // merge project libraries
+        for library in build_config.libraries {
+            if library != '' && library !in lib.libraries {
+                lib.libraries << library
+            }
+        }
+    }
+
+    for mut tool in build_config.tools {
+        // merge include dirs
+        for inc in build_config.include_dirs {
+            if inc != '' && inc !in tool.include_dirs {
+                tool.include_dirs << inc
+            }
+        }
+        // merge cflags
+        for flag in build_config.cflags {
+            if flag != '' && flag !in tool.cflags {
+                tool.cflags << flag
+            }
+        }
+        // merge ldflags
+        for flag in build_config.ldflags {
+            if flag != '' && flag !in tool.ldflags {
+                tool.ldflags << flag
+            }
+        }
+        // merge project libraries
+        for library in build_config.libraries {
+            if library != '' && library !in tool.libraries {
+                tool.libraries << library
+            }
+        }
+    }
+    
     return build_config
 }
 
@@ -630,7 +686,7 @@ pub fn build_shared_compiler_command(source_file string, object_file string, bui
     }
     
     // Add standard flags
-    cmd += ' -Wall -Wextra -std=c++17'
+    cmd += ' -Wall -Wextra'
     
     // Add global CFLAGS
     for flag in build_config.cflags {
@@ -691,7 +747,10 @@ pub fn build_shared_linker_command(object_files []string, library_name string, o
     }
     
     // Set output name (with platform-specific extension)
-    mut lib_name := library_name
+    // Use only the basename of the library to avoid duplicating path segments
+    parts := library_name.split('/')
+    base_name := if parts.len > 0 { parts[parts.len - 1] } else { library_name }
+    mut lib_name := base_name
     $if windows {
         lib_name += '.dll'
     } $else {
@@ -772,7 +831,7 @@ pub fn build_compiler_command(source_file string, object_file string, build_conf
     }
     
     // Add standard flags
-    cmd += ' -Wall -Wextra -std=c++17'
+    cmd += ' -Wall -Wextra'
     
     // Add custom CFLAGS
     for flag in build_config.cflags {