add more docs and clean up exception, json modules (#92)

src/context.rs

@@ -1,3 +1,4 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
 use crate::isolate::Isolate;
 use crate::support::Opaque;
 use crate::Local;
@@ -11,6 +12,8 @@ extern "C" {
   fn v8__Context__Global(this: *mut Context) -> *mut Object;
 }
 
+/// A sandboxed execution context with its own set of built-in objects and
+/// functions.
 #[repr(C)]
 pub struct Context(Opaque);
 
@@ -34,11 +37,17 @@ impl Context {
     unsafe { Local::from_raw(v8__Context__Global(&mut *self)).unwrap() }
   }
 
+  /// Enter this context.  After entering a context, all code compiled
+  /// and run is compiled and run in this context.  If another context
+  /// is already entered, this old context is saved so it can be
+  /// restored when the new context is exited.
   pub fn enter(&mut self) {
     // TODO: enter/exit should be controlled by a scope.
     unsafe { v8__Context__Enter(self) };
   }
 
+  /// Exit this context.  Exiting the current context restores the
+  /// context that was in place when entering the current context.
   pub fn exit(&mut self) {
     // TODO: enter/exit should be controlled by a scope.
     unsafe { v8__Context__Exit(self) };

src/exception.rs

@@ -54,52 +54,44 @@ impl Message {
   }
 }
 
-/// Create new error objects by calling the corresponding error object
-/// constructor with the message.
-pub mod Exception {
-  use super::*;
-
-  /// Creates an error message for the given exception.
-  /// Will try to reconstruct the original stack trace from the exception value,
-  /// or capture the current stack trace if not available.
-  pub fn CreateMessage(
+/// Creates an error message for the given exception.
+/// Will try to reconstruct the original stack trace from the exception value,
+/// or capture the current stack trace if not available.
+pub fn create_message(
   isolate: &Isolate,
   mut exception: Local<Value>,
-  ) -> Local<Message> {
+) -> Local<Message> {
   unsafe {
     Local::from_raw(v8__Exception__CreateMessage(isolate, &mut *exception))
   }
   .unwrap()
-  }
+}
 
-  /// Returns the original stack trace that was captured at the creation time
-  /// of a given exception, or an empty handle if not available.
-  pub fn GetStackTrace(
+/// Returns the original stack trace that was captured at the creation time
+/// of a given exception, or an empty handle if not available.
+pub fn get_stack_trace(
   mut exception: Local<Value>,
-  ) -> Option<Local<StackTrace>> {
+) -> Option<Local<StackTrace>> {
   unsafe { Local::from_raw(v8__Exception__GetStackTrace(&mut *exception)) }
-  }
+}
 
-  pub fn RangeError(mut message: Local<String>) -> Local<Value> {
-    unsafe { Local::from_raw(v8__Exception__RangeError(&mut *message)) }
-      .unwrap()
-  }
+pub fn range_error(mut message: Local<String>) -> Local<Value> {
+  unsafe { Local::from_raw(v8__Exception__RangeError(&mut *message)) }.unwrap()
+}
 
-  pub fn ReferenceError(mut message: Local<String>) -> Local<Value> {
+pub fn reference_error(mut message: Local<String>) -> Local<Value> {
   unsafe { Local::from_raw(v8__Exception__ReferenceError(&mut *message)) }
     .unwrap()
-  }
-
-  pub fn SyntaxError(mut message: Local<String>) -> Local<Value> {
-    unsafe { Local::from_raw(v8__Exception__SyntaxError(&mut *message)) }
-      .unwrap()
-  }
-
-  pub fn TypeError(mut message: Local<String>) -> Local<Value> {
-    unsafe { Local::from_raw(v8__Exception__TypeError(&mut *message)) }.unwrap()
-  }
-
-  pub fn Error(mut message: Local<String>) -> Local<Value> {
-    unsafe { Local::from_raw(v8__Exception__Error(&mut *message)) }.unwrap()
-  }
+}
+
+pub fn syntax_error(mut message: Local<String>) -> Local<Value> {
+  unsafe { Local::from_raw(v8__Exception__SyntaxError(&mut *message)) }.unwrap()
+}
+
+pub fn type_error(mut message: Local<String>) -> Local<Value> {
+  unsafe { Local::from_raw(v8__Exception__TypeError(&mut *message)) }.unwrap()
+}
+
+pub fn error(mut message: Local<String>) -> Local<Value> {
+  unsafe { Local::from_raw(v8__Exception__Error(&mut *message)) }.unwrap()
 }

src/isolate.rs

@@ -1,15 +1,15 @@
-use std::ops::Deref;
-use std::ops::DerefMut;
-use std::ptr::NonNull;
-
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
 use crate::array_buffer::Allocator;
-use crate::exception::Message;
 use crate::promise::PromiseRejectMessage;
 use crate::support::Delete;
 use crate::support::Opaque;
 use crate::support::UniqueRef;
 use crate::Local;
+use crate::Message;
 use crate::Value;
+use std::ops::Deref;
+use std::ops::DerefMut;
+use std::ptr::NonNull;
 
 type MessageCallback = extern "C" fn(Local<Message>, Local<Value>);
 
@@ -44,6 +44,12 @@ extern "C" {
 }
 
 #[repr(C)]
+/// Isolate represents an isolated instance of the V8 engine.  V8 isolates have
+/// completely separate states.  Objects from one isolate must not be used in
+/// other isolates.  The embedder can create multiple isolates and use them in
+/// parallel in multiple threads.  An isolate can be entered by at most one
+/// thread at any given time.  The Locker/Unlocker API must be used to
+/// synchronize.
 pub struct Isolate(Opaque);
 
 impl Isolate {

src/json.rs

@@ -1,5 +1,5 @@
-#![allow(non_snake_case)]
-
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+//! A JSON Parser and Stringifier.
 use crate::Context;
 use crate::Local;
 use crate::String;
@@ -16,29 +16,22 @@ extern "C" {
   ) -> *mut String;
 }
 
-/// A JSON Parser and Stringifier
-pub mod JSON {
-  use super::*;
-
-  /// Tries to parse the string `json_string` and returns it as value if
-  /// successful.
-  pub fn Parse(
+/// Tries to parse the string `json_string` and returns it as value if
+/// successful.
+pub fn parse(
   mut context: Local<Context>,
   mut json_string: Local<String>,
-  ) -> Option<Local<Value>> {
-    unsafe {
-      Local::from_raw(v8__JSON__Parse(&mut *context, &mut *json_string))
-    }
-  }
+) -> Option<Local<Value>> {
+  unsafe { Local::from_raw(v8__JSON__Parse(&mut *context, &mut *json_string)) }
+}
 
-  /// Tries to stringify the JSON-serializable object `json_object` and returns
-  /// it as string if successful.
-  pub fn Stringify(
+/// Tries to stringify the JSON-serializable object `json_object` and returns
+/// it as string if successful.
+pub fn stringify(
   mut context: Local<Context>,
   mut json_object: Local<Value>,
-  ) -> Option<Local<String>> {
+) -> Option<Local<String>> {
   unsafe {
     Local::from_raw(v8__JSON__Stringify(&mut *context, &mut *json_object))
   }
-  }
 }

src/lib.rs

@@ -14,7 +14,6 @@ mod exception;
 mod function;
 mod handle_scope;
 mod isolate;
-mod json;
 mod local;
 mod locker;
 mod number;
@@ -28,6 +27,7 @@ mod value;
 
 pub mod array_buffer;
 pub mod inspector;
+pub mod json;
 pub mod platform;
 // This module is intentionally named "V8" rather than "v8" to match the
 // C++ namespace "v8::V8".
@@ -35,13 +35,11 @@ pub mod platform;
 pub mod V8;
 
 pub use context::Context;
-pub use exception::Exception;
-pub use exception::Message;
+pub use exception::*;
 pub use function::{Function, FunctionCallbackInfo, FunctionTemplate};
 pub use handle_scope::HandleScope;
 pub use isolate::Isolate;
 pub use isolate::OwnedIsolate;
-pub use json::JSON;
 pub use local::Local;
 pub use locker::Locker;
 pub use number::{Integer, Number};

src/locker.rs

@@ -1,14 +1,6 @@
-use std::mem::MaybeUninit;
-
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
 use crate::isolate::Isolate;
-
-// class Locker {
-//  public:
-//    explicit Locker(Isolate* isolate);
-//    ~Locker();
-//    static bool IsLocked(Isolate* isolate);
-//    static bool IsActive();
-// }
+use std::mem::MaybeUninit;
 
 extern "C" {
   fn v8__Locker__CONSTRUCT(buf: &mut MaybeUninit<Locker>, isolate: &Isolate);
@@ -16,9 +8,14 @@ extern "C" {
 }
 
 #[repr(C)]
+/// v8::Locker is a scoped lock object. While it's active, i.e. between its
+/// construction and destruction, the current thread is allowed to use the locked
+/// isolate. V8 guarantees that an isolate can be locked by at most one thread at
+/// any time. In other words, the scope of a v8::Locker is a critical section.
 pub struct Locker([usize; 2]);
 
 impl Locker {
+  /// Initialize Locker for a given Isolate.
   pub fn new(isolate: &Isolate) -> Self {
     let mut buf = MaybeUninit::<Self>::uninit();
     unsafe {

tests/test_api.rs

@@ -307,19 +307,19 @@ fn exception() {
     context.enter();
     let reference = "This is a test error";
     let local = v8_str(&isolate, reference);
-    v8::Exception::RangeError(local);
-    v8::Exception::ReferenceError(local);
-    v8::Exception::SyntaxError(local);
-    v8::Exception::TypeError(local);
-    let exception = v8::Exception::Error(local);
-    let msg = v8::Exception::CreateMessage(&isolate, exception);
+    v8::range_error(local);
+    v8::reference_error(local);
+    v8::syntax_error(local);
+    v8::type_error(local);
+    let exception = v8::error(local);
+    let msg = v8::create_message(&isolate, exception);
     let msg_string = msg.get();
     let rust_msg_string = msg_string.to_rust_string_lossy(&isolate);
     assert_eq!(
       "Uncaught Error: This is a test error".to_string(),
       rust_msg_string
     );
-    assert!(v8::Exception::GetStackTrace(exception).is_none());
+    assert!(v8::get_stack_trace(exception).is_none());
     context.exit();
   });
   drop(locker);
@@ -339,10 +339,10 @@ fn json() {
     let mut context = v8::Context::new(&isolate);
     context.enter();
     let json_string = v8_str(&isolate, "{\"a\": 1, \"b\": 2}");
-    let maybe_value = v8::JSON::Parse(context, json_string);
+    let maybe_value = v8::json::parse(context, json_string);
     assert!(maybe_value.is_some());
     let value = maybe_value.unwrap();
-    let maybe_stringified = v8::JSON::Stringify(context, value);
+    let maybe_stringified = v8::json::stringify(context, value);
     assert!(maybe_stringified.is_some());
     let stringified = maybe_stringified.unwrap();
     let rust_str = stringified.to_rust_string_lossy(&isolate);