Add warning to CMakeDeps2 for module cmake_find_mode property (#18230)

Changelog: Omit
Docs: Omit

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Author: memsharded

conan/tools/cmake/cmakedeps2/cmakedeps.py

@@ -4,7 +4,7 @@
 
 from jinja2 import Template
 
-from conan.api.output import Color
+from conan.api.output import Color, ConanOutput
 from conan.errors import ConanException
 from conan.internal import check_duplicated_generator
 from conan.internal.api.install.generators import relativize_path
@@ -59,6 +59,12 @@ def _content(self):
             cmake_find_mode = cmake_find_mode.lower()
             if cmake_find_mode == FIND_MODE_NONE:
                 continue
+            if cmake_find_mode == FIND_MODE_MODULE:
+                ConanOutput(self._conanfile.ref).warning("CMakeConfigDeps does not support "
+                                                         f"module find mode in {dep}.\n"
+                                                         f"Config mode will be used regardless.",
+                                                         # Should this be risk?
+                                                         warn_tag="deprecated")
 
             if require.direct:
                 direct_deps.append((require, dep))

test/integration/toolchains/cmake/cmakedeps2/test_cmakedeps.py

@@ -1,6 +1,8 @@
 import re
 import textwrap
 
+import pytest
+
 from conan.test.assets.genconanfile import GenConanfile
 from conan.test.utils.tools import TestClient
 
@@ -338,3 +340,22 @@ def test(self):
             "main/test_package/conanfile.py":test_package})
     c.run("create ./dependent/ --name=dependent --version=0.1 -c tools.cmake.cmakedeps:new=will_break_next")
     c.run("create ./main/ --name=pkg --version=0.1 -c tools.cmake.cmakedeps:new=will_break_next")
+
+
+def test_cmake_find_mode_deprecated():
+    tc = TestClient()
+    dep = textwrap.dedent("""
+        from conan import ConanFile
+        class Pkg(ConanFile):
+            name = "dep"
+            version = "0.1"
+            def package_info(self):
+                # Having both is ok as the user expects that config would
+                # be generated nonetheless
+                self.cpp_info.set_property("cmake_find_mode", "module")
+        """)
+    tc.save({"conanfile.py": dep})
+    tc.run("create .")
+    args = f"-g CMakeDeps -c tools.cmake.cmakedeps:new={new_value}"
+    tc.run(f"install --requires=dep/0.1 {args}")
+    assert "CMakeConfigDeps does not support module find mode"