add set_base to rules

7 files changed, 85 insertions, 2 deletions

diff --git a/tests/apis/rules_override_cxx/src/main.xx b/tests/apis/rules_override_cxx/src/main.xx
new file mode 100644
index 000000000..d612d8782
--- /dev/null
+++ b/tests/apis/rules_override_cxx/src/main.xx
@@ -0,0 +1,6 @@
+#include <stdio.h>
+
+int main(int argc, char** argv)
+{
+    return 0;
+}
diff --git a/tests/apis/rules_override_cxx/xmake.lua b/tests/apis/rules_override_cxx/xmake.lua
new file mode 100644
index 000000000..0dc2261ca
--- /dev/null
+++ b/tests/apis/rules_override_cxx/xmake.lua
@@ -0,0 +1,26 @@
+rule("xx.build")
+    set_base("c++.build")
+    set_extensions(".xx")
+    on_load(function (target)
+        local sourcebatch = target:sourcebatches()["xx.build"]
+        sourcebatch.sourcekind = "cxx"
+        sourcebatch.objectfiles = {}
+        sourcebatch.dependfiles = {}
+        for _, sourcefile in ipairs(sourcebatch.sourcefiles) do
+            local objectfile = target:objectfile(sourcefile)
+            local dependfile = target:dependfile(objectfile)
+            table.insert(sourcebatch.objectfiles, objectfile)
+            table.insert(sourcebatch.dependfiles, dependfile)
+        end
+        target:add("cxxflags", "-x c++")
+    end)
+
+rule("xx")
+    set_base("c++")
+    add_deps("xx.build")
+
+target("test")
+    set_kind("binary")
+    add_rules("xx")
+    add_files("src/*.xx")
+
diff --git a/tests/apis/rules_override_order/src/main.cc b/tests/apis/rules_override_order/src/main.cc
new file mode 100644
index 000000000..d612d8782
--- /dev/null
+++ b/tests/apis/rules_override_order/src/main.cc
@@ -0,0 +1,6 @@
+#include <stdio.h>
+
+int main(int argc, char** argv)
+{
+    return 0;
+}
diff --git a/tests/apis/rules_override_order/xmake.lua b/tests/apis/rules_override_order/xmake.lua
new file mode 100644
index 000000000..61b42a943
--- /dev/null
+++ b/tests/apis/rules_override_order/xmake.lua
@@ -0,0 +1,15 @@
+rule("cppfront")
+    set_extensions(".cpp2")
+    on_build_files(function (target, batchjobs, sourcebatch, opt)
+        print("on_build_files")
+    end, {batch = true, distcc = true})
+
+rule("xx")
+    set_base("c++")
+    add_deps("cppfront", {order = true})
+
+target("test")
+    set_kind("binary")
+    add_rules("xx")
+    add_files("src/*.cc")
+
diff --git a/tests/projects/c++/unity_build/src/test.cpp b/tests/projects/c++/unity_build/src/test.cpp
new file mode 100644
index 000000000..27d41ee50
--- /dev/null
+++ b/tests/projects/c++/unity_build/src/test.cpp
@@ -0,0 +1,8 @@
+#include "header.h"
+
+int main(int argc, char** argv) 
+{
+    std::string s("xmake");
+    printf("hello %s!\n", s.c_str());
+    return 0;
+}
diff --git a/xmake/core/project/project.lua b/xmake/core/project/project.lua
index f48a45205..3c4c39232 100644
--- a/xmake/core/project/project.lua
+++ b/xmake/core/project/project.lua
@@ -326,6 +326,10 @@ function project._load_rules()
     for _, instance in pairs(instances)  do
         instance._DEPS      = instance._DEPS or {}
         instance._ORDERDEPS = instance._ORDERDEPS or {}
+        local base = instance:get("base")
+        if base then
+            instance._BASE = instances[base]
+        end
         project._load_deps(instance, instances, instance._DEPS, instance._ORDERDEPS, {instance:name()})
     end
     return rules
diff --git a/xmake/core/project/rule.lua b/xmake/core/project/rule.lua
index 599294a45..841203c9d 100644
--- a/xmake/core/project/rule.lua
+++ b/xmake/core/project/rule.lua
@@ -150,6 +150,7 @@ function rule.apis()
             "rule.set_extensions"
         ,   "rule.set_sourcekinds"
         ,   "rule.set_kind"
+        ,   "rule.set_base"
             -- rule.add_xxx
         ,   "rule.add_deps"
         ,   "rule.add_imports"
@@ -214,14 +215,31 @@ function rule.new(name, info)
     return instance
 end
 
+-- get the base rule
+function rule:base()
+    return self._BASE
+end
+
 -- get the rule info
 function rule:get(name)
-    return self._INFO:get(name)
+    local value = self._INFO:get(name)
+    if value == nil and self:base() then
+        value = self:base():get(name)
+    end
+    if value ~= nil then
+        return value
+    end
 end
 
 -- get the extra configuration
 function rule:extraconf(name, item, key)
-    return self._INFO:extraconf(name, item, key)
+    local value = self._INFO:extraconf(name, item, key)
+    if value == nil and self:base() then
+        value = self:base():extraconf(name)
+    end
+    if value ~= nil then
+        return value
+    end
 end
 
 -- get the rule name