Add support for custom commands

Author: mrexodia

docs/cmake-toml.md

@@ -246,6 +246,24 @@ link-options = [""] # linker flags
 private-link-options = [""]
 precompile-headers = [""] # precompiled headers
 private-precompile-headers = [""]
+dependencies = [""] # add_dependencies(target ...)
+
+# Keys below are for type = "custom" (add_custom_target)
+all = false
+command = ["${CMAKE_COMMAND}", "-E", "echo", "Hello"] # one command line
+commands = [ # multiple command lines
+    ["${CMAKE_COMMAND}", "-E", "echo", "First"],
+    ["${CMAKE_COMMAND}", "-E", "echo", "Second"],
+]
+depends = ["generated.txt"] # add_custom_target(... DEPENDS ...)
+byproducts = ["generated.txt"]
+working-directory = "${CMAKE_CURRENT_BINARY_DIR}"
+comment = "Run custom target"
+job-pool = "pool"
+job-server-aware = true
+verbatim = true
+uses-terminal = true
+command-expand-lists = true
 
 cmake-before = """
 message(STATUS "CMake injected before the target")
@@ -263,6 +281,51 @@ CXX_STANDARD_REQUIRED = true
 FOLDER = "MyFolder"
 ```
 
+### Custom commands
+
+Use `[[target.<name>.custom-command]]` to map directly to [`add_custom_command`](https://cmake.org/cmake/help/latest/command/add_custom_command.html). A custom command can use either the `OUTPUT` form or the `TARGET` form:
+
+```toml
+# OUTPUT form (add_custom_command(OUTPUT ...))
+[[target.mytarget.custom-command]]
+condition = "mycondition"
+outputs = ["${CMAKE_CURRENT_BINARY_DIR}/generated.cpp"]
+command = [
+    "${CMAKE_COMMAND}",
+    "-DOUTPUT=${CMAKE_CURRENT_BINARY_DIR}/generated.cpp",
+    "-P",
+    "${CMAKE_CURRENT_SOURCE_DIR}/cmake/generate.cmake",
+]
+depends = ["cmake/generate.cmake"]
+byproducts = ["${CMAKE_CURRENT_BINARY_DIR}/generated.hpp"]
+main-dependency = "cmake/generate.cmake"
+implicit-depends = [["CXX", "src/input.idl"]]
+working-directory = "${CMAKE_CURRENT_BINARY_DIR}"
+comment = "Generate source"
+depfile = "${CMAKE_CURRENT_BINARY_DIR}/generated.d"
+job-pool = "pool"
+job-server-aware = true
+verbatim = true
+append = false
+uses-terminal = false
+codegen = false
+command-expand-lists = false
+depends-explicit-only = false
+
+# TARGET form (add_custom_command(TARGET ...))
+[[target.mytarget.custom-command]]
+build-event = "post-build" # pre-build, pre-link, post-build
+command = ["${CMAKE_COMMAND}", "-E", "touch", "${CMAKE_CURRENT_BINARY_DIR}/post-build.stamp"]
+byproducts = ["${CMAKE_CURRENT_BINARY_DIR}/post-build.stamp"]
+working-directory = "${CMAKE_CURRENT_BINARY_DIR}"
+comment = "Post-build step"
+verbatim = true
+command-expand-lists = false
+uses-terminal = false
+```
+
+For each custom command entry, exactly one of `outputs` or `build-event` is required.
+
 A table mapping the cmkr features to the relevant CMake construct and the relevant documentation pages:
 
 | cmkr | CMake construct | Description |
@@ -279,6 +342,9 @@ A table mapping the cmkr features to the relevant CMake construct and the releva
 | `link-libraries` | [`target_link_libraries`](https://cmake.org/cmake/help/latest/command/target_link_libraries.html) | Adds library dependencies. Use `::mylib` to make sure a target exists. |
 | `link-options` | [`target_link_options`](https://cmake.org/cmake/help/latest/command/target_link_options.html) | Adds linker flags. |
 | `precompile-headers` | [`target_precompile_headers`](https://cmake.org/cmake/help/latest/command/target_precompile_headers.html) | Specifies precompiled headers. |
+| `dependencies` | [`add_dependencies`](https://cmake.org/cmake/help/latest/command/add_dependencies.html) | Adds target-level dependencies. |
+| `type = "custom"` + custom target keys | [`add_custom_target`](https://cmake.org/cmake/help/latest/command/add_custom_target.html) | Creates a custom target with command/dependency options. |
+| `[[target.<name>.custom-command]]` | [`add_custom_command`](https://cmake.org/cmake/help/latest/command/add_custom_command.html) | Supports both `OUTPUT` and `TARGET` forms. |
 | `properties` | [`set_target_properties`](https://cmake.org/cmake/help/latest/command/set_target_properties.html) | See [properties on targets](https://cmake.org/cmake/help/latest/manual/cmake-properties.7.html#properties-on-targets) for more information. |
 
 The default [visibility](/basics) is as follows:
@@ -342,4 +408,4 @@ files = ["content/my.png"]
 dirs = ["include"]
 configs = ["Release", "Debug"]
 optional = false
-```
+```

docs/examples/custom-command.md

@@ -0,0 +1,66 @@
+---
+# Automatically generated from tests/custom-command/cmake.toml - DO NOT EDIT
+layout: default
+title: Tests add_custom_command and add_custom_target support
+permalink: /examples/custom-command
+parent: Examples
+nav_order: 12
+---
+
+# Tests add_custom_command and add_custom_target support
+
+
+
+```toml
+[project]
+name = "custom-command"
+description = "Tests add_custom_command and add_custom_target support"
+
+[target.custom-command]
+type = "executable"
+sources = ["src/main.cpp"]
+include-directories = ["${CMAKE_CURRENT_BINARY_DIR}/generated"]
+
+[[target.custom-command.custom-command]]
+outputs = ["${CMAKE_CURRENT_BINARY_DIR}/generated/generated.cpp"]
+byproducts = ["${CMAKE_CURRENT_BINARY_DIR}/generated/generated.hpp"]
+depends = ["cmake/generate_source.cmake"]
+command = [
+    "${CMAKE_COMMAND}",
+    "-DOUTPUT_CPP=${CMAKE_CURRENT_BINARY_DIR}/generated/generated.cpp",
+    "-DOUTPUT_HPP=${CMAKE_CURRENT_BINARY_DIR}/generated/generated.hpp",
+    "-P",
+    "${CMAKE_CURRENT_SOURCE_DIR}/cmake/generate_source.cmake",
+]
+comment = "Generate source files"
+verbatim = true
+
+[[target.custom-command.custom-command]]
+build-event = "post-build"
+command = [
+    "${CMAKE_COMMAND}",
+    "-E",
+    "touch",
+    "${CMAKE_CURRENT_BINARY_DIR}/custom-command-post-build.stamp",
+]
+byproducts = ["${CMAKE_CURRENT_BINARY_DIR}/custom-command-post-build.stamp"]
+comment = "Create a post-build stamp file"
+verbatim = true
+
+[target.custom-codegen]
+type = "custom"
+all = true
+command = [
+    "${CMAKE_COMMAND}",
+    "-E",
+    "touch",
+    "${CMAKE_CURRENT_BINARY_DIR}/custom-target.stamp",
+]
+byproducts = ["${CMAKE_CURRENT_BINARY_DIR}/custom-target.stamp"]
+comment = "Run custom target"
+verbatim = true
+```
+
+
+
+<sup><sub>This page was automatically generated from [tests/custom-command/cmake.toml](https://github.com/build-cpp/cmkr/tree/main/tests/custom-command/cmake.toml).</sub></sup>

include/project_parser.hpp

@@ -74,6 +74,105 @@ enum TargetType {
 extern const char *targetTypeNames[target_last];
 
 struct Target {
+    struct CustomTarget {
+        bool has_all = false;
+        bool all = false;
+
+        bool has_command = false;
+        bool has_commands = false;
+        std::vector<std::vector<std::string>> commands;
+        std::vector<std::string> depends;
+        std::vector<std::string> byproducts;
+
+        bool has_working_directory = false;
+        std::string working_directory;
+
+        bool has_comment = false;
+        std::string comment;
+
+        bool has_job_pool = false;
+        std::string job_pool;
+
+        bool has_job_server_aware = false;
+        bool job_server_aware = false;
+
+        bool has_verbatim = false;
+        bool verbatim = false;
+
+        bool has_uses_terminal = false;
+        bool uses_terminal = false;
+
+        bool has_command_expand_lists = false;
+        bool command_expand_lists = false;
+
+        bool empty() const {
+            return !has_all && !has_command && !has_commands && commands.empty() && depends.empty() && byproducts.empty() && !has_working_directory &&
+                   !has_comment &&
+                   !has_job_pool && !has_job_server_aware && !has_verbatim && !has_uses_terminal && !has_command_expand_lists;
+        }
+    };
+
+    struct CustomCommand {
+        struct ImplicitDependency {
+            std::string language;
+            std::string file;
+        };
+
+        std::string condition;
+        std::vector<std::vector<std::string>> commands;
+
+        std::vector<std::string> outputs;
+        std::string build_event;
+
+        bool has_append = false;
+        bool append = false;
+
+        bool has_main_dependency = false;
+        std::string main_dependency;
+
+        std::vector<std::string> depends;
+        std::vector<std::string> byproducts;
+        std::vector<ImplicitDependency> implicit_depends;
+
+        bool has_working_directory = false;
+        std::string working_directory;
+
+        bool has_comment = false;
+        std::string comment;
+
+        bool has_depfile = false;
+        std::string depfile;
+
+        bool has_job_pool = false;
+        std::string job_pool;
+
+        bool has_job_server_aware = false;
+        bool job_server_aware = false;
+
+        bool has_verbatim = false;
+        bool verbatim = false;
+
+        bool has_uses_terminal = false;
+        bool uses_terminal = false;
+
+        bool has_codegen = false;
+        bool codegen = false;
+
+        bool has_command_expand_lists = false;
+        bool command_expand_lists = false;
+
+        bool has_depends_explicit_only = false;
+        bool depends_explicit_only = false;
+
+        bool is_output_form() const {
+            return !outputs.empty();
+        }
+
+        bool is_target_form() const {
+            return !build_event.empty();
+        }
+    };
+
     std::string name;
     TargetType type = target_last;
     std::string type_name;
@@ -107,6 +206,9 @@ struct Target {
 
     ConditionVector dependencies;
 
+    CustomTarget custom_target;
+    std::vector<CustomCommand> custom_commands;
+
     std::string condition;
     std::string alias;
     Condition<tsl::ordered_map<std::string, std::string>> properties;