Factor out annotated type generics to separate template

Summary:
The new `{{> lib/type_generics}}` template generates the `<T>` in Vec<T> and BTreeSet<T>, and the `<T, U>` in BTreeMap<T, U>, and in custom types specified through `rust.Type`.

Beyond deduplicating the existing 2 uses (field types `{{field:type_rust}}`, service method argument types `{{type:rust}}`), I need to use this same logic a third time for typedef types `{{typedef:rust_type}}` in {D68909054}.

Reviewed By: emersonford

Differential Revision: D68927538

fbshipit-source-id: 9ceee895f092de98d97bf3222749cb86f1b3f618

Author: David Tolnay

third-party/thrift/src/thrift/compiler/generate/templates/rust/lib/annfieldtype.mustache

@@ -27,25 +27,12 @@
 }}{{/type:struct}}{{!
 }}{{#type:enum}}{{enum:package}}::{{enum:rust_name}}{{/type:enum}}{{!
 }}{{#type:list?}}
-    }}::std::vec::Vec<{{#type:list_elem_type}}{{> lib/type}}{{/type:list_elem_type}}>{{!
+    }}::std::vec::Vec{{> lib/type_generics}}{{!
 }}{{/type:list?}}{{!
 }}{{#type:set?}}{{!
-    }}::{{field:type_rust}}{{!
-    }}<{{!
-        }}{{#type:set_elem_type}}{{!
-        }}{{#type:floating_point?}}::fbthrift::export::OrderedFloat<{{> lib/type}}>{{/type:floating_point?}}{{!
-        }}{{^type:floating_point?}}{{> lib/type}}{{/type:floating_point?}}{{!
-        }}{{/type:set_elem_type}}{{!
-    }}>{{!
+    }}::{{field:type_rust}}{{> lib/type_generics}}{{!
 }}{{/type:set?}}{{!
 }}{{#type:map?}}{{!
-    }}::{{field:type_rust}}{{!
-    }}<{{!
-        }}{{#type:key_type}}{{!
-        }}{{#type:floating_point?}}::fbthrift::export::OrderedFloat<{{> lib/type}}>{{/type:floating_point?}}{{!
-        }}{{^type:floating_point?}}{{> lib/type}}{{/type:floating_point?}}{{!
-        }}{{/type:key_type}}, {{!
-        }}{{#type:value_type}}{{> lib/type}}{{/type:value_type}}{{!
-    }}>{{!
+    }}::{{field:type_rust}}{{> lib/type_generics}}{{!
 }}{{/type:map?}}{{!
 }}

third-party/thrift/src/thrift/compiler/generate/templates/rust/lib/rawtype.mustache

@@ -48,27 +48,16 @@
     }}{{enum:package}}::{{enum:rust_name}}{{!
 }}{{/type:enum}}{{!
 }}{{#type:list?}}{{!
-    }}::std::vec::Vec<{{#type:list_elem_type}}{{> lib/type}}{{/type:list_elem_type}}>{{!
+    }}::std::vec::Vec{{> lib/type_generics}}{{!
 }}{{/type:list?}}{{!
 }}{{#type:set?}}{{!
     }}{{#type:rust}}::{{type:rust}}{{/type:rust}}{{!
     }}{{^type:rust}}::std::collections::BTreeSet{{/type:rust}}{{!
-    }}<{{!
-        }}{{#type:set_elem_type}}{{!
-        }}{{#type:floating_point?}}::fbthrift::export::OrderedFloat<{{> lib/type}}>{{/type:floating_point?}}{{!
-        }}{{^type:floating_point?}}{{> lib/type}}{{/type:floating_point?}}{{!
-        }}{{/type:set_elem_type}}{{!
-    }}>{{!
+    }}{{> lib/type_generics}}{{!
 }}{{/type:set?}}{{!
 }}{{#type:map?}}{{!
     }}{{#type:rust}}::{{type:rust}}{{/type:rust}}{{!
     }}{{^type:rust}}::std::collections::BTreeMap{{/type:rust}}{{!
-    }}<{{!
-        }}{{#type:key_type}}{{!
-        }}{{#type:floating_point?}}::fbthrift::export::OrderedFloat<{{> lib/type}}>{{/type:floating_point?}}{{!
-        }}{{^type:floating_point?}}{{> lib/type}}{{/type:floating_point?}}{{!
-        }}{{/type:key_type}}, {{!
-        }}{{#type:value_type}}{{> lib/type}}{{/type:value_type}}{{!
-    }}>{{!
+    }}{{> lib/type_generics}}{{!
 }}{{/type:map?}}{{!
 }}

third-party/thrift/src/thrift/compiler/generate/templates/rust/lib/type_generics.mustache

@@ -0,0 +1,43 @@
+{{!
+
+  Copyright (c) Meta Platforms, Inc. and affiliates.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+      http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  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.
+
+}}{{#type:list?}}{{!
+    }}<{{!
+        }}{{#type:list_elem_type}}{{!
+            }}{{> lib/type}}{{!
+        }}{{/type:list_elem_type}}{{!
+    }}>{{!
+}}{{/type:list?}}{{!
+}}{{#type:set?}}{{!
+    }}<{{!
+        }}{{#type:set_elem_type}}{{!
+            }}{{#type:floating_point?}}::fbthrift::export::OrderedFloat<{{> lib/type}}>{{/type:floating_point?}}{{!
+            }}{{^type:floating_point?}}{{> lib/type}}{{/type:floating_point?}}{{!
+        }}{{/type:set_elem_type}}{{!
+    }}>{{!
+}}{{/type:set?}}{{!
+}}{{#type:map?}}{{!
+    }}<{{!
+        }}{{#type:key_type}}{{!
+            }}{{#type:floating_point?}}::fbthrift::export::OrderedFloat<{{> lib/type}}>{{/type:floating_point?}}{{!
+            }}{{^type:floating_point?}}{{> lib/type}}{{/type:floating_point?}}{{!
+        }}{{/type:key_type}}, {{!
+        }}{{#type:value_type}}{{!
+            }}{{> lib/type}}{{!
+        }}{{/type:value_type}}{{!
+    }}>{{!
+}}{{/type:map?}}{{!
+}}