Cache well known symbols

[HalidOdat]

#704 (comment)

It changes the following:

• Add Context::well_known_symbols() method.
• Add WellKnownSymbols struct
• Add getters for the symbols to WellKnownSymbols struct

With this PR we can now do:

let mut context = Context::new();

let iterator = context.well_known_symbols().iterator_symbol();

instead of:

let mut context = Context::new();

let iterator = context.global_object().get_field("Symbol").get_field("iterator").as_symbol().unwrap();

Also there is a problem with this ^, what if we override Symbol object like:

globalThis.Symbol = 10;

Now the above code will panic, we should have a way to access the well known symbols without being tied to the global bindings.

What do you think? @joshwd36

[codecov]

Codecov Report

Merging #706 into master will increase coverage by 0.03%.
The diff coverage is 80.00%.

@@            Coverage Diff             @@
##           master     #706      +/-   ##
==========================================
+ Coverage   71.69%   71.72%   +0.03%     
==========================================
  Files         199      199              
  Lines       13865    13937      +72     
==========================================
+ Hits         9941     9997      +56     
- Misses       3924     3940      +16     

Impacted Files	Coverage Δ
boa/src/builtins/symbol/mod.rs	80.13% <79.31%> (-2.98%)	⬇️
boa/src/context.rs	61.45% <100.00%> (+0.65%)	⬆️

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[joshwd36]

What do you think? @joshwd36

I think this is a good way of doing it, definitely makes getting symbols from the Rust side a lot easier.

[github-actions]

Benchmark for 2c62562

Click to view benchmark

Test	PR Benchmark	Master Benchmark	%
Arithmetic operations (Execution)	373.2±8.83ns	380.6±20.59ns	-1.94%
Arithmetic operations (Full)	266.1±8.59µs	257.9±7.89µs	+3.18%
Array access (Execution)	8.6±0.38µs	8.9±0.29µs	-3.37%
Array access (Full)	290.4±14.92µs	287.9±12.15µs	+0.87%
Array creation (Execution)	3.2±0.10ms	3.4±0.09ms	-5.88%
Array creation (Full)	3.5±0.15ms	3.6±0.12ms	-2.78%
Array pop (Execution)	1127.7±55.83µs	1228.3±48.02µs	-8.19%
Array pop (Full)	1630.1±88.87µs	1652.6±36.07µs	-1.36%
Boolean Object Access (Execution)	5.0±0.20µs	5.2±0.25µs	-3.85%
Boolean Object Access (Full)	277.4±15.99µs	273.0±11.75µs	+1.61%
Clean js (Execution)	749.7±24.66µs	778.4±32.60µs	-3.69%
Clean js (Full)	1062.1±37.35µs	1088.3±80.63µs	-2.41%
Clean js (Parser)	38.0±1.34µs	38.8±1.93µs	-2.06%
Create Realm	508.7±24.64ns	487.3±17.02ns	+4.39%
Dynamic Object Property Access (Execution)	5.8±0.49µs	5.9±0.27µs	-1.69%
Dynamic Object Property Access (Full)	293.2±34.88µs	277.3±12.03µs	+5.73%
Expression (Parser)	7.1±0.35µs	6.9±0.73µs	+2.90%
Fibonacci (Execution)	915.5±62.46µs	919.2±32.70µs	-0.40%
Fibonacci (Full)	1197.4±30.35µs	1205.8±37.57µs	-0.70%
For loop (Execution)	23.7±1.17µs	23.9±0.91µs	-0.84%
For loop (Full)	301.8±9.42µs	299.7±10.27µs	+0.70%
For loop (Parser)	18.4±0.45µs	18.4±0.59µs	0.00%
Goal Symbols (Parser)	12.6±0.82µs	12.3±0.26µs	+2.44%
Hello World (Parser)	3.2±0.09µs	3.2±0.14µs	0.00%
Long file (Parser)	814.8±58.35ns	818.7±42.31ns	-0.48%
Mini js (Execution)	672.0±25.97µs	700.8±24.59µs	-4.11%
Mini js (Full)	973.8±20.46µs	984.0±45.75µs	-1.04%
Mini js (Parser)	34.7±10.39µs	34.0±1.27µs	+2.06%
Number Object Access (Execution)	3.9±0.12µs	4.3±0.34µs	-9.30%
Number Object Access (Full)	275.8±10.16µs	272.4±10.51µs	+1.25%
Object Creation (Execution)	5.1±0.44µs	5.2±0.59µs	-1.92%
Object Creation (Full)	279.1±11.59µs	269.7±7.64µs	+3.49%
RegExp (Execution)	70.6±3.73µs	71.1±6.37µs	-0.70%
RegExp (Full)	363.8±14.28µs	357.1±17.88µs	+1.88%
RegExp Literal (Execution)	74.9±2.95µs	74.6±4.51µs	+0.40%
RegExp Literal (Full)	358.0±10.65µs	355.0±14.87µs	+0.85%
RegExp Literal Creation (Execution)	70.4±3.16µs	70.3±2.46µs	+0.14%
RegExp Literal Creation (Full)	352.8±18.80µs	353.1±37.57µs	-0.08%
Static Object Property Access (Execution)	5.4±0.97µs	5.3±0.17µs	+1.89%
Static Object Property Access (Full)	272.4±11.21µs	275.7±9.64µs	-1.20%
String Object Access (Execution)	7.2±0.36µs	7.8±0.49µs	-7.69%
String Object Access (Full)	288.1±24.54µs	274.9±10.54µs	+4.80%
String comparison (Execution)	6.7±0.22µs	6.7±0.15µs	0.00%
String comparison (Full)	282.4±7.71µs	275.8±10.27µs	+2.39%
String concatenation (Execution)	5.5±0.19µs	5.7±0.48µs	-3.51%
String concatenation (Full)	276.6±12.19µs	272.1±14.80µs	+1.65%
String copy (Execution)	4.2±0.36µs	4.4±0.40µs	-4.55%
String copy (Full)	267.7±10.01µs	263.5±7.36µs	+1.59%
Symbols (Execution)	3.4±0.15µs	3.5±0.09µs	-2.86%
Symbols (Full)	250.8±10.79µs	250.0±11.00µs	+0.32%

[github-actions]

Benchmark for 92935f0

Click to view benchmark

Test	PR Benchmark	Master Benchmark	%
Arithmetic operations (Execution)	423.8±17.90ns	407.3±19.83ns	+4.05%
Arithmetic operations (Full)	281.7±9.41µs	287.2±23.92µs	-1.92%
Array access (Execution)	9.1±0.34µs	9.5±0.34µs	-4.21%
Array access (Full)	310.8±17.86µs	306.2±11.73µs	+1.50%
Array creation (Execution)	3.4±0.14ms	3.6±0.11ms	-5.56%
Array creation (Full)	3.7±0.07ms	3.8±0.09ms	-2.63%
Array pop (Execution)	1195.0±30.47µs	1271.7±48.67µs	-6.03%
Array pop (Full)	1724.8±46.79µs	1761.3±53.65µs	-2.07%
Boolean Object Access (Execution)	5.4±0.25µs	5.5±0.28µs	-1.82%
Boolean Object Access (Full)	300.5±17.72µs	301.5±13.84µs	-0.33%
Clean js (Execution)	795.4±26.41µs	814.1±20.77µs	-2.30%
Clean js (Full)	1118.5±26.11µs	1148.3±32.20µs	-2.60%
Clean js (Parser)	41.3±1.89µs	41.1±1.75µs	+0.49%
Create Realm	505.3±18.58ns	506.8±16.43ns	-0.30%
Dynamic Object Property Access (Execution)	6.1±0.25µs	6.3±0.20µs	-3.17%
Dynamic Object Property Access (Full)	306.2±38.59µs	299.8±8.51µs	+2.13%
Expression (Parser)	7.4±0.24µs	7.3±0.23µs	+1.37%
Fibonacci (Execution)	997.7±38.41µs	1001.2±39.29µs	-0.35%
Fibonacci (Full)	1286.0±48.99µs	1275.2±37.73µs	+0.85%
For loop (Execution)	25.3±1.30µs	25.1±0.79µs	+0.80%
For loop (Full)	325.3±11.99µs	321.4±14.62µs	+1.21%
For loop (Parser)	19.8±1.57µs	19.6±0.95µs	+1.02%
Goal Symbols (Parser)	13.1±0.58µs	13.3±0.39µs	-1.50%
Hello World (Parser)	3.4±0.20µs	3.3±0.11µs	+3.03%
Long file (Parser)	866.2±25.42ns	855.6±38.83ns	+1.24%
Mini js (Execution)	717.1±19.58µs	730.8±24.76µs	-1.87%
Mini js (Full)	1045.8±62.11µs	1060.0±44.21µs	-1.34%
Mini js (Parser)	36.0±1.54µs	36.1±2.06µs	-0.28%
Number Object Access (Execution)	4.3±0.19µs	4.4±0.18µs	-2.27%
Number Object Access (Full)	291.3±13.68µs	301.5±71.23µs	-3.38%
Object Creation (Execution)	5.3±0.23µs	5.5±0.26µs	-3.64%
Object Creation (Full)	298.8±9.09µs	291.1±14.63µs	+2.65%
RegExp (Execution)	73.3±2.26µs	73.7±2.91µs	-0.54%
RegExp (Full)	386.3±10.59µs	389.4±13.37µs	-0.80%
RegExp Literal (Execution)	79.6±5.96µs	79.6±4.11µs	0.00%
RegExp Literal (Full)	387.9±12.62µs	381.8±14.53µs	+1.60%
RegExp Literal Creation (Execution)	74.8±3.57µs	75.2±2.79µs	-0.53%
RegExp Literal Creation (Full)	371.6±11.45µs	376.2±22.93µs	-1.22%
Static Object Property Access (Execution)	5.5±0.21µs	5.8±0.27µs	-5.17%
Static Object Property Access (Full)	296.9±8.93µs	295.2±8.71µs	+0.58%
String Object Access (Execution)	7.9±0.25µs	7.8±0.24µs	+1.28%
String Object Access (Full)	302.1±12.79µs	302.1±27.64µs	0.00%
String comparison (Execution)	7.1±0.25µs	7.4±0.36µs	-4.05%
String comparison (Full)	300.9±8.77µs	302.5±13.77µs	-0.53%
String concatenation (Execution)	5.9±0.29µs	6.0±0.61µs	-1.67%
String concatenation (Full)	293.6±9.91µs	293.8±9.60µs	-0.07%
String copy (Execution)	4.5±0.14µs	4.9±0.19µs	-8.16%
String copy (Full)	290.0±14.40µs	286.6±10.41µs	+1.19%
Symbols (Execution)	3.6±0.11µs	3.7±0.15µs	-2.70%
Symbols (Full)	271.4±18.64µs	262.6±9.83µs	+3.35%

[github-actions]

Benchmark for ebeb17c

Click to view benchmark

Test	PR Benchmark	Master Benchmark	%
Arithmetic operations (Execution)	382.9±13.49ns	367.5±13.22ns	+4.19%
Arithmetic operations (Full)	262.3±10.97µs	263.8±11.44µs	-0.57%
Array access (Execution)	9.1±0.50µs	8.7±0.49µs	+4.60%
Array access (Full)	285.1±8.76µs	289.1±10.39µs	-1.38%
Array creation (Execution)	3.3±0.11ms	3.3±0.11ms	0.00%
Array creation (Full)	3.5±0.08ms	3.5±0.10ms	0.00%
Array pop (Execution)	1149.9±206.90µs	1181.6±40.35µs	-2.68%
Array pop (Full)	1648.1±60.66µs	1639.1±98.40µs	+0.55%
Boolean Object Access (Execution)	5.0±0.19µs	5.0±0.22µs	0.00%
Boolean Object Access (Full)	277.2±10.64µs	283.3±12.11µs	-2.15%
Clean js (Execution)	755.5±36.60µs	762.1±27.87µs	-0.87%
Clean js (Full)	1039.6±33.30µs	1061.8±50.41µs	-2.09%
Clean js (Parser)	38.0±1.62µs	37.2±1.96µs	+2.15%
Create Realm	506.7±29.01ns	465.1±16.19ns	+8.94%
Dynamic Object Property Access (Execution)	5.9±0.22µs	5.8±0.28µs	+1.72%
Dynamic Object Property Access (Full)	288.4±11.81µs	290.8±14.73µs	-0.83%
Expression (Parser)	6.9±0.35µs	6.9±1.10µs	0.00%
Fibonacci (Execution)	969.1±31.02µs	937.3±38.31µs	+3.39%
Fibonacci (Full)	1203.7±64.64µs	1231.7±48.21µs	-2.27%
For loop (Execution)	25.3±1.14µs	23.4±1.31µs	+8.12%
For loop (Full)	299.6±11.81µs	306.8±12.45µs	-2.35%
For loop (Parser)	18.2±0.83µs	18.5±0.76µs	-1.62%
Goal Symbols (Parser)	12.4±0.67µs	12.3±0.66µs	+0.81%
Hello World (Parser)	3.1±0.10µs	3.1±0.19µs	0.00%
Long file (Parser)	783.6±27.51ns	780.5±24.79ns	+0.40%
Mini js (Execution)	681.4±22.35µs	684.6±30.59µs	-0.47%
Mini js (Full)	983.0±36.15µs	972.6±25.83µs	+1.07%
Mini js (Parser)	35.5±1.16µs	33.3±1.56µs	+6.61%
Number Object Access (Execution)	3.9±0.15µs	3.9±0.18µs	0.00%
Number Object Access (Full)	280.4±8.72µs	278.8±9.72µs	+0.57%
Object Creation (Execution)	5.0±0.20µs	5.1±0.19µs	-1.96%
Object Creation (Full)	283.3±11.16µs	277.2±8.88µs	+2.20%
RegExp (Execution)	73.9±3.08µs	70.2±3.76µs	+5.27%
RegExp (Full)	382.2±13.54µs	362.8±17.15µs	+5.35%
RegExp Literal (Execution)	76.1±3.24µs	73.5±3.21µs	+3.54%
RegExp Literal (Full)	361.9±10.07µs	356.8±12.18µs	+1.43%
RegExp Literal Creation (Execution)	74.6±2.81µs	70.2±7.00µs	+6.27%
RegExp Literal Creation (Full)	354.9±14.56µs	351.3±13.89µs	+1.02%
Static Object Property Access (Execution)	5.4±0.28µs	5.3±0.28µs	+1.89%
Static Object Property Access (Full)	293.3±8.38µs	278.5±10.28µs	+5.31%
String Object Access (Execution)	7.4±0.33µs	7.4±0.39µs	0.00%
String Object Access (Full)	284.2±11.32µs	291.0±13.18µs	-2.34%
String comparison (Execution)	6.7±0.35µs	6.8±0.23µs	-1.47%
String comparison (Full)	292.5±9.51µs	282.8±14.67µs	+3.43%
String concatenation (Execution)	5.7±0.26µs	5.7±0.38µs	0.00%
String concatenation (Full)	284.7±9.78µs	273.9±9.68µs	+3.94%
String copy (Execution)	4.3±0.17µs	4.3±0.17µs	0.00%
String copy (Full)	287.3±14.90µs	271.4±14.25µs	+5.86%
Symbols (Execution)	3.6±0.12µs	3.5±0.14µs	+2.86%
Symbols (Full)	247.8±8.41µs	249.2±12.49µs	-0.56%