Make some types work with Default

Summary: Especially in testing, it can be tedious to create a lot of objects. Add some default implmentations so that `..Default::default()` syntax works

Reviewed By: bobyangyf

Differential Revision: D38452374

fbshipit-source-id: 5df299cf8fe8b6c37ca156c24e4ee6a7a6986e82

Author: Natalie Jameson

starlark/src/tests/docstring.rs

@@ -169,10 +169,7 @@ def f4(a: "string") -> "string":
                 }),
             },
         ],
-        ret: Return {
-            docs: None,
-            typ: None,
-        },
+        ..Default::default()
     }));
 
     let expected_f3 = Some(DocItem::Function(Function {
@@ -288,7 +285,6 @@ fn test_module_docs_return() {
     use crate::values::docs::DocString;
     use crate::values::docs::Function;
     use crate::values::docs::Module;
-    use crate::values::docs::Return;
 
     let mut a = Assert::new();
     let mod_a = r#"
@@ -341,14 +337,7 @@ def f1():
     let m2_docs = m2.module_documentation();
     let m3_docs = m3.module_documentation();
 
-    let empty_function = Some(DocItem::Function(Function {
-        docs: None,
-        params: vec![],
-        ret: Return {
-            docs: None,
-            typ: None,
-        },
-    }));
+    let empty_function = Some(DocItem::Function(Function::default()));
 
     let expected_m1 = ModuleDocs {
         module: Some(DocItem::Module(Module {
@@ -363,11 +352,7 @@ Some extra details can go here,
         members: hashmap! {
             "f1".to_owned() => Some(DocItem::Function(Function {
                 docs: DocString::from_docstring(DocStringKind::Starlark, "This is a function summary"),
-                params: vec![],
-                ret: Return {
-                    docs: None,
-                    typ: None,
-                },
+                ..Default::default()
             })),
             "f2".to_owned() => empty_function.clone(),
         },

starlark/src/values/docs/mod.rs

@@ -54,7 +54,7 @@ fn indent_trimmed(s: &str, prefix: &str) -> String {
 }
 
 /// The documentation provided by a user for a specific module, object, function, etc.
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, Trace)]
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, Trace, Default)]
 pub struct DocString {
     /// The first line of a doc string. This has whitespace trimmed from it.
     pub summary: String,
@@ -355,7 +355,7 @@ impl DocString {
 }
 
 /// Line / column for where in a file a symbol is.
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, Default)]
 pub struct Pos {
     /// Line number, zero based.
     pub line: usize,
@@ -364,7 +364,7 @@ pub struct Pos {
 }
 
 /// The file a symbol resides in, and if available its location within that file.
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, Default)]
 pub struct Location {
     /// `path` is a string that can be passed into `load()` statements.
     pub path: String,
@@ -373,7 +373,7 @@ pub struct Location {
 }
 
 /// The main identifier for a symbol.
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, Default)]
 pub struct Identifier {
     /// The name of the symbol (e.g. the function name, a name or path for a module, etc).
     pub name: String,
@@ -382,14 +382,14 @@ pub struct Identifier {
 }
 
 /// The type of a given parameter, field, etc.
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, Default)]
 pub struct Type {
     /// The type string that one would find in a starlark expression.
     pub raw_type: String,
 }
 
 /// Documents a full module.
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, Default)]
 pub struct Module {
     /// In general, this should be the first statement of a loaded file, if that statement is
     /// a string literal.
@@ -406,7 +406,7 @@ impl Module {
 }
 
 /// Documents a single function.
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, Default)]
 pub struct Function {
     /// Documentation for the function. If parsed, this should generally be the first statement
     /// of a function's body if that statement is a string literal. Any sections like "Args:",
@@ -669,7 +669,7 @@ impl Param {
 }
 
 /// Details about the return value of a function.
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, Default)]
 pub struct Return {
     /// Extra semantic details around the returned value's meaning.
     pub docs: Option<DocString>,
@@ -684,7 +684,7 @@ impl Return {
 }
 
 /// A single property of an object. These are explicitly not functions (see [`Member`]).
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, Default)]
 pub struct Property {
     pub docs: Option<DocString>,
     #[serde(rename = "type")]
@@ -724,7 +724,7 @@ pub enum Member {
 }
 
 /// An object with named functions/properties.
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, Default)]
 pub struct Object {
     pub docs: Option<DocString>,
     /// Name and details of each member of this object.