Allow for js property inspection #1876
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This annotation generates a `toJSON` and `toString` implementation for generated JavaScript classes which display all readable properties available via the class or its getters This is useful because wasm-bindgen classes currently serialize to display one value named `ptr`, which does not model the properties of the struct in Rust This annotation addresses #1857
`#[wasm_bindgen(inspectable)]` now generates an implementation of `[util.inspect.custom]` for the Node.js target only. This implementation causes `console.log` and friends to yield the same class-style output, but with all readable fields of the Rust struct displayed
crates/cli-support/src/js/mod.rs
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| toString() {{ | ||
| return JSON.stringify({readable_properties}); |
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Could this perhaps be JSON.stringify(this.toJSON()) to avoid duplication?
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I implemented it that way originally, but I thought it may be confusing if a struct providing its own toJSON had the side effect of changing toString and [util.custom.inspect]. If it’s documented then it shouldn’t be an issue though. I’ll take your advice and mention it in the guide!
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Yeah sounds good to me!
| name: "inspect".to_string(), | ||
| }, | ||
| fields: Vec::new(), | ||
| })?; |
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The return value of this is a String which I think should be used instead of import.custom below
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I'm not sure if I can, this import gives me "inspect" back but the symbol name has to be "inspect.custom"… Do you know if there's another method I should try to get the symbol name in a variable?
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Oh sorry what I mean is that below instead of [inspect.custom] you'll want to do [{}.custom] where {} is the return value of this function. That way if the identifier inspect is imported from elsewhere it'll still work.
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That makes sense! I've updated it
crates/cli-support/src/js/mod.rs
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| dst.push_str( | ||
| &format!(" | ||
| [inspect.custom]() {{ | ||
| return Object.assign(Object.create({{constructor: this.constructor}}), {readable_properties}); |
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Could this use this.toJSON() instead of duplicating the readable properties?
Generated `toString` and `[util.inspect.custom]` methods now call `toJSON` to reduce duplication
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Thanks again for this! |
This was missed in PR #1876
This resolves #1857 by introducing
#[wasm_bindgen(inspectable)]. This annotation:toJSON, which can be overridden if the user defines their owntoJSONtoString, which can be overridden if the user defines their owntoString[util.inspect.custom]for the Node.js target only, which applies toconsole.logand friendsIts allows all public fields/getters of the Rust struct to be shown when logging or serializing the generated class in JavaScript (
console.log,JSON.stringify, etc.)Let me know if this needs any additional work! I thought about using "display," "debug," or "serialize" to mimic the similar derivations in Rust, but I decided "inspectable" was more clear