Demo Gen default value parameter attributes (#667)

* Started drafting default value parameter attributes * Add support for default values in the renderer * Formatting * Update snapshots * Parse ints and floats * Formatting
rust-diplomat · Sep 3, 2024 · 5ccea38 · 5ccea38
1 parent d7ad173
commit 5ccea38
Show file tree

Hide file tree

Showing 12 changed files with 192 additions and 80 deletions.
diff --git a/core/src/hir/attrs.rs b/core/src/hir/attrs.rs
@@ -54,11 +54,17 @@ pub struct Attrs {
 #[non_exhaustive]
 #[derive(Clone, Default, Debug)]
 pub struct DemoInputCFG {
-    /// `#[diplomat(input(label = "..."))]`
+    /// `#[diplomat::demo(input(label = "..."))]`
     /// Label that this input parameter should have. Let demo_gen pick a valid name if this is empty.
     ///
     /// For instance <label for="v">Number Here</label><input name="v"/>
     pub label: String,
+
+    /// `#[diplomat::demo(input(default_value = "..."))]`
+    /// Sets the default value for a parameter.
+    ///
+    /// Should ALWAYS be a string. The HTML renderer is expected to do validation for us.
+    pub default_value: String,
 }
 
 #[non_exhaustive]
@@ -372,6 +378,24 @@ impl Attrs {
                                 let s: syn::LitStr = value.parse()?;
                                 this.demo_attrs.input_cfg.label = s.value();
                                 Ok(())
+                            } else if meta.path.is_ident("default_value") {
+                                let value = meta.value()?;
+
+                                let str_val: String;
+
+                                let ahead = value.lookahead1();
+                                if ahead.peek(syn::LitFloat) {
+                                    let s: syn::LitFloat = value.parse()?;
+                                    str_val = s.base10_parse::<f64>()?.to_string();
+                                } else if ahead.peek(syn::LitInt) {
+                                    let s: syn::LitInt = value.parse()?;
+                                    str_val = s.base10_parse::<i64>()?.to_string();
+                                } else {
+                                    let s: syn::LitStr = value.parse()?;
+                                    str_val = s.value();
+                                }
+                                this.demo_attrs.input_cfg.default_value = str_val;
+                                Ok(())
                             } else {
                                 Err(meta.error(format!(
                                     "Unsupported ident {:?}",

diff --git a/core/src/hir/snapshots/diplomat_core__hir__elision__tests__elision_in_struct.snap b/core/src/hir/snapshots/diplomat_core__hir__elision__tests__elision_in_struct.snap
@@ -50,6 +50,7 @@ Method {
                     external: false,
                     input_cfg: DemoInputCFG {
                         label: "",
+                        default_value: "",
                     },
                 },
             },
@@ -101,6 +102,7 @@ Method {
                     external: false,
                     input_cfg: DemoInputCFG {
                         label: "",
+                        default_value: "",
                     },
                 },
             },
@@ -125,6 +127,7 @@ Method {
             external: false,
             input_cfg: DemoInputCFG {
                 label: "",
+                default_value: "",
             },
         },
     },

diff --git a/core/src/hir/snapshots/diplomat_core__hir__elision__tests__simple_mod.snap b/core/src/hir/snapshots/diplomat_core__hir__elision__tests__simple_mod.snap
@@ -53,6 +53,7 @@ TypeContext {
                             external: false,
                             input_cfg: DemoInputCFG {
                                 label: "",
+                                default_value: "",
                             },
                         },
                     },
@@ -108,6 +109,7 @@ TypeContext {
                                     external: false,
                                     input_cfg: DemoInputCFG {
                                         label: "",
+                                        default_value: "",
                                     },
                                 },
                             },
@@ -151,6 +153,7 @@ TypeContext {
                             external: false,
                             input_cfg: DemoInputCFG {
                                 label: "",
+                                default_value: "",
                             },
                         },
                     },
@@ -172,6 +175,7 @@ TypeContext {
                     external: false,
                     input_cfg: DemoInputCFG {
                         label: "",
+                        default_value: "",
                     },
                 },
             },
@@ -234,6 +238,7 @@ TypeContext {
                             external: false,
                             input_cfg: DemoInputCFG {
                                 label: "",
+                                default_value: "",
                             },
                         },
                     },
@@ -291,6 +296,7 @@ TypeContext {
                                     external: false,
                                     input_cfg: DemoInputCFG {
                                         label: "",
+                                        default_value: "",
                                     },
                                 },
                             },
@@ -327,6 +333,7 @@ TypeContext {
                                     external: false,
                                     input_cfg: DemoInputCFG {
                                         label: "",
+                                        default_value: "",
                                     },
                                 },
                             },
@@ -364,6 +371,7 @@ TypeContext {
                             external: false,
                             input_cfg: DemoInputCFG {
                                 label: "",
+                                default_value: "",
                             },
                         },
                     },
@@ -385,6 +393,7 @@ TypeContext {
                     external: false,
                     input_cfg: DemoInputCFG {
                         label: "",
+                        default_value: "",
                     },
                 },
             },
@@ -429,6 +438,7 @@ TypeContext {
                     external: false,
                     input_cfg: DemoInputCFG {
                         label: "",
+                        default_value: "",
                     },
                 },
             },

diff --git a/docs/demo_gen.md b/docs/demo_gen.md
@@ -192,6 +192,28 @@ export const RenderInfo = {
 };
 ```
 
+The exact structure of `RenderInfo` is:
+
+```js
+export const RenderInfo = {
+    termini: {
+        "functionName": {
+            func: jsFunctionToCall, // Always present.
+            funcName: "jsFunctionToCall", // String value of the function name. Always present.
+            parameters: [ // Always present.
+                {
+                    name: "Param Name", // Always present. Modified by `#[diplomat::demo(input(label = "..."))]`
+                    type: "type_name", // Always present. Could be: string, number, boolean, Array<string>, Array<number>, Array<boolean>, or some specific JS binding class name (i.e., MyEnum).
+                    // In your HTML renderer, you should generally assume that any type that is not a primitive is an enum. #[diplomat::demo(external)] parameters are also exposed here, so be prepared to include carve-outs for those exceptions.
+                    defaultValue: "defaultValue" // Only present if `#[diplomat::demo(input(default_value = "..."))]` is present.
+                }
+            ]
+        }
+    }
+};
+
+```
+
 #### Example Part 3
 
 For `FixedDecimalFormatter.formatWrite`, let's look at the rust definition again:

diff --git a/example/demo_gen/demo/index.mjs b/example/demo_gen/demo/index.mjs
diff --git a/example/demo_gen/demo/rendering/rendering.mjs b/example/demo_gen/demo/rendering/rendering.mjs
diff --git a/example/src/decimal.rs b/example/src/decimal.rs
@@ -33,7 +33,7 @@ pub mod ffi {
     pub struct FixedDecimalFormatterOptions {
         #[diplomat::demo(input(label = "ICU4X Fixed Decimal Grouping Strategy"))]
         pub grouping_strategy: FixedDecimalGroupingStrategy,
-        #[diplomat::demo(input(label = "Useless Config (Ignore)"))]
+        #[diplomat::demo(input(label = "Useless Config (Ignore)", default_value = "true"))]
         pub some_other_config: bool,
     }
 

diff --git a/example/src/fixed_decimal.rs b/example/src/fixed_decimal.rs
@@ -13,7 +13,8 @@ pub mod ffi {
         /// Construct an [`FixedDecimal`] from an integer.
         #[diplomat::attr(auto, constructor)]
         pub fn new(
-            #[diplomat::demo(input(label = "ICU4XFixedDecimal Value"))] v: i32,
+            #[diplomat::demo(input(label = "ICU4XFixedDecimal Value", default_value = 1000))]
+            v: i32,
         ) -> Box<FixedDecimal> {
             Box::new(FixedDecimal(fixed_decimal::FixedDecimal::from(v)))
         }