add testcase for bad things with add_project_dependencies

Test that add_project_dependencies() can only be used before build targets
have been declared.  Also test that one cannot use override_dependency
on a superproject to inject a superproject's build products into the
subproject.  This would violate the rule that build products cannot be used
with add_project_dependencies() (similar to e.g. compiler.has_function),
so check that meson detects the situation correctly.

test cases/failing/124 override and add_project_dependency/inc/lib.h

@@ -0,0 +1,2 @@
+#pragma once
+void f(void);

test cases/failing/124 override and add_project_dependency/lib.c

@@ -0,0 +1,3 @@
+#include <stdio.h>
+#include "lib.h"
+void f() {puts("hello");}

test cases/failing/124 override and add_project_dependency/meson.build

@@ -0,0 +1,8 @@
+project('super', 'c')
+
+inc = include_directories('inc')
+lib = static_library('sneaky', 'lib.c', include_directories: inc)
+meson.override_dependency('sneaky',
+  declare_dependency(link_with: lib, include_directories: inc))
+
+subproject('a')

test cases/failing/124 override and add_project_dependency/subprojects/a/meson.build

@@ -0,0 +1,10 @@
+project('a', 'c')
+
+dep = dependency('sneaky')
+
+# does not work
+add_project_dependencies(dep, language: 'c')
+executable('prog', 'prog.c')
+
+# this would work instead:
+# executable('prog', 'prog.c', dependencies: dep)

test cases/failing/124 override and add_project_dependency/subprojects/a/prog.c

@@ -0,0 +1,6 @@
+#include "lib.h"
+
+int main() {
+    f();
+    return 0;
+}

test cases/failing/124 override and add_project_dependency/test.json

@@ -0,0 +1,7 @@
+{
+  "stdout": [
+    {
+      "line": "test cases/failing/124 override and add_project_dependency/subprojects/a/meson.build:6:0: ERROR: Dependencies must be external dependencies"
+    }
+  ]
+}

test cases/failing/125 targets before add_project_dependency/inc/lib.h

@@ -0,0 +1,2 @@
+#pragma once
+void f(void);

test cases/failing/125 targets before add_project_dependency/lib.c

@@ -0,0 +1,3 @@
+#include <stdio.h>
+#include "lib.h"
+void f() {puts("hello");}

test cases/failing/125 targets before add_project_dependency/meson.build

@@ -0,0 +1,5 @@
+project('test', 'c')
+
+static_library('lib', 'lib.c')
+inc = include_directories('inc')
+add_project_dependencies(declare_dependency(include_directories: inc), language: 'c')

test cases/failing/125 targets before add_project_dependency/test.json

@@ -0,0 +1,7 @@
+{
+  "stdout": [
+    {
+      "line": "test cases/failing/125 targets before add_project_dependency/meson.build:5:0: ERROR: Tried to use 'add_project_dependencies' after a build target has been declared."
+    }
+  ]
+}