Implement FetchPackage; a simple wrapper around FindOrFetch.

FetchPackage calls FindOrFetch, but sets USE_SYSTEM_PACKAGE to OFF
(i.e. do not find, just fetch). It also sets EXCLUDE_FROM_ALL.

PiperOrigin-RevId: 822565180
Change-Id: I70476f57b8d3371cefd02e840add279423913f3f

cmake/FindOrFetch.cmake

@@ -11,7 +11,7 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-#
+
 #.rst:
 # FindOrFetch
 # ----------------------
@@ -56,10 +56,7 @@
 # https://cmake.org/cmake/help/latest/module/FetchContent.html#variables to
 # override this macro behaviour.
 
-if(COMMAND FindOrFetch)
+if(NOT COMMAND FindOrFetch)
-  return()
-endif()
-
   macro(FindOrFetch)
     if(NOT FetchContent)
       include(FetchContent)
@@ -138,3 +135,58 @@ macro(FindOrFetch)
       message(CHECK_PASS "found")
     endif()
   endmacro()
+endif()
+
+
+#.rst:
+# FetchPackage
+# ----------------------
+#
+# Fetches a package from a Git repository in order to satisfy dependencies.
+#
+#   FetchPackage([PACKAGE_NAME [name]]
+#               [GIT_REPO [repo]]
+#               [GIT_TAG [tag]]
+#               [PATCH_COMMAND [cmd] [args]]
+#              )
+#
+# The command has the following parameters:
+#
+# Arguments:
+#  - ``PACKAGE_NAME`` name of the package.
+#  - ``GIT_REPO`` git repository to fetch the library from.
+#  - ``GIT_TAG`` tag reference when fetching the library from the git repo.
+#  - ``PATCH_COMMAND`` Specifies a custom command to patch the sources after an
+#    update. See https://cmake.org/cmake/help/latest/module/ExternalProject.html#command:externalproject_add
+#    for details on the parameter.
+#  - ``TARGETS`` (optional) list of targets to be satisfied. If any of these
+#    targets are not currently defined, this macro will attempt to fetch the
+#    package. If not specified, the package name will be used as the target.
+#
+# Note: This is a wrapper around FindOrFetch that sets EXCLUDE_FROM_ALL and
+# USE_SYSTEM_PACKAGE to OFF.
+if(NOT COMMAND FetchPackage)
+  function(FetchPackage)
+    cmake_parse_arguments(
+      _ARGS
+      "EXCLUDE_FROM_ALL"
+      "PACKAGE_NAME;GIT_REPO;GIT_TAG"
+      "PATCH_COMMAND;TARGETS"
+      ${ARGN}
+    )
+    if(NOT _ARGS_TARGETS)
+      set(_ARGS_TARGETS ${_ARGS_PACKAGE_NAME})
+    endif()
+
+    FindOrFetch(
+      PACKAGE_NAME ${_ARGS_PACKAGE_NAME}
+      LIBRARY_NAME ${_ARGS_PACKAGE_NAME}
+      GIT_REPO ${_ARGS_GIT_REPO}
+      GIT_TAG ${_ARGS_GIT_TAG}
+      PATCH_COMMAND ${_ARGS_PATCH_COMMAND}
+      TARGETS ${_ARGS_TARGETS}
+      USE_SYSTEM_PACKAGE OFF
+      EXCLUDE_FROM_ALL
+    )
+  endfunction()
+endif()

sample/cmake/FindOrFetch.cmake

@@ -11,7 +11,7 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-#
+
 #.rst:
 # FindOrFetch
 # ----------------------
@@ -56,10 +56,7 @@
 # https://cmake.org/cmake/help/latest/module/FetchContent.html#variables to
 # override this macro behaviour.
 
-if(COMMAND FindOrFetch)
+if(NOT COMMAND FindOrFetch)
-  return()
-endif()
-
   macro(FindOrFetch)
     if(NOT FetchContent)
       include(FetchContent)
@@ -138,3 +135,58 @@ macro(FindOrFetch)
       message(CHECK_PASS "found")
     endif()
   endmacro()
+endif()
+
+
+#.rst:
+# FetchPackage
+# ----------------------
+#
+# Fetches a package from a Git repository in order to satisfy dependencies.
+#
+#   FetchPackage([PACKAGE_NAME [name]]
+#               [GIT_REPO [repo]]
+#               [GIT_TAG [tag]]
+#               [PATCH_COMMAND [cmd] [args]]
+#              )
+#
+# The command has the following parameters:
+#
+# Arguments:
+#  - ``PACKAGE_NAME`` name of the package.
+#  - ``GIT_REPO`` git repository to fetch the library from.
+#  - ``GIT_TAG`` tag reference when fetching the library from the git repo.
+#  - ``PATCH_COMMAND`` Specifies a custom command to patch the sources after an
+#    update. See https://cmake.org/cmake/help/latest/module/ExternalProject.html#command:externalproject_add
+#    for details on the parameter.
+#  - ``TARGETS`` (optional) list of targets to be satisfied. If any of these
+#    targets are not currently defined, this macro will attempt to fetch the
+#    package. If not specified, the package name will be used as the target.
+#
+# Note: This is a wrapper around FindOrFetch that sets EXCLUDE_FROM_ALL and
+# USE_SYSTEM_PACKAGE to OFF.
+if(NOT COMMAND FetchPackage)
+  function(FetchPackage)
+    cmake_parse_arguments(
+      _ARGS
+      "EXCLUDE_FROM_ALL"
+      "PACKAGE_NAME;GIT_REPO;GIT_TAG"
+      "PATCH_COMMAND;TARGETS"
+      ${ARGN}
+    )
+    if(NOT _ARGS_TARGETS)
+      set(_ARGS_TARGETS ${_ARGS_PACKAGE_NAME})
+    endif()
+
+    FindOrFetch(
+      PACKAGE_NAME ${_ARGS_PACKAGE_NAME}
+      LIBRARY_NAME ${_ARGS_PACKAGE_NAME}
+      GIT_REPO ${_ARGS_GIT_REPO}
+      GIT_TAG ${_ARGS_GIT_TAG}
+      PATCH_COMMAND ${_ARGS_PATCH_COMMAND}
+      TARGETS ${_ARGS_TARGETS}
+      USE_SYSTEM_PACKAGE OFF
+      EXCLUDE_FROM_ALL
+    )
+  endfunction()
+endif()

simulate/cmake/FindOrFetch.cmake

@@ -11,7 +11,7 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-#
+
 #.rst:
 # FindOrFetch
 # ----------------------
@@ -56,10 +56,7 @@
 # https://cmake.org/cmake/help/latest/module/FetchContent.html#variables to
 # override this macro behaviour.
 
-if(COMMAND FindOrFetch)
+if(NOT COMMAND FindOrFetch)
-  return()
-endif()
-
   macro(FindOrFetch)
     if(NOT FetchContent)
       include(FetchContent)
@@ -138,3 +135,58 @@ macro(FindOrFetch)
       message(CHECK_PASS "found")
     endif()
   endmacro()
+endif()
+
+
+#.rst:
+# FetchPackage
+# ----------------------
+#
+# Fetches a package from a Git repository in order to satisfy dependencies.
+#
+#   FetchPackage([PACKAGE_NAME [name]]
+#               [GIT_REPO [repo]]
+#               [GIT_TAG [tag]]
+#               [PATCH_COMMAND [cmd] [args]]
+#              )
+#
+# The command has the following parameters:
+#
+# Arguments:
+#  - ``PACKAGE_NAME`` name of the package.
+#  - ``GIT_REPO`` git repository to fetch the library from.
+#  - ``GIT_TAG`` tag reference when fetching the library from the git repo.
+#  - ``PATCH_COMMAND`` Specifies a custom command to patch the sources after an
+#    update. See https://cmake.org/cmake/help/latest/module/ExternalProject.html#command:externalproject_add
+#    for details on the parameter.
+#  - ``TARGETS`` (optional) list of targets to be satisfied. If any of these
+#    targets are not currently defined, this macro will attempt to fetch the
+#    package. If not specified, the package name will be used as the target.
+#
+# Note: This is a wrapper around FindOrFetch that sets EXCLUDE_FROM_ALL and
+# USE_SYSTEM_PACKAGE to OFF.
+if(NOT COMMAND FetchPackage)
+  function(FetchPackage)
+    cmake_parse_arguments(
+      _ARGS
+      "EXCLUDE_FROM_ALL"
+      "PACKAGE_NAME;GIT_REPO;GIT_TAG"
+      "PATCH_COMMAND;TARGETS"
+      ${ARGN}
+    )
+    if(NOT _ARGS_TARGETS)
+      set(_ARGS_TARGETS ${_ARGS_PACKAGE_NAME})
+    endif()
+
+    FindOrFetch(
+      PACKAGE_NAME ${_ARGS_PACKAGE_NAME}
+      LIBRARY_NAME ${_ARGS_PACKAGE_NAME}
+      GIT_REPO ${_ARGS_GIT_REPO}
+      GIT_TAG ${_ARGS_GIT_TAG}
+      PATCH_COMMAND ${_ARGS_PATCH_COMMAND}
+      TARGETS ${_ARGS_TARGETS}
+      USE_SYSTEM_PACKAGE OFF
+      EXCLUDE_FROM_ALL
+    )
+  endfunction()
+endif()