Made String.prototype.lastIndexOf() spec compliant

[HalidOdat]

It changes the following:

• Made String.prototype.lastIndexOf() spec complaint
• Added tests

[codecov]

Codecov Report

Merging #598 into master will increase coverage by 0.24%.
The diff coverage is 97.40%.

@@            Coverage Diff             @@
##           master     #598      +/-   ##
==========================================
+ Coverage   71.26%   71.51%   +0.24%     
==========================================
  Files         177      177              
  Lines       11598    11650      +52     
==========================================
+ Hits         8265     8331      +66     
+ Misses       3333     3319      -14     

Impacted Files	Coverage Δ
boa/src/builtins/string/mod.rs	50.54% <87.50%> (+3.67%)	⬆️
boa/src/builtins/string/tests.rs	100.00% <100.00%> (ø)

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[github-actions]

Benchmark for 10c5635

Click to view benchmark

Test	PR Benchmark	Master Benchmark	%
Arithmetic operations (Execution)	350.5±8.86ns	363.6±11.74ns	-3.60%
Arithmetic operations (Full)	175.2±5.20µs	174.4±3.81µs	+0.46%
Array access (Execution)	8.8±0.32µs	8.8±0.35µs	0.00%
Array access (Full)	192.7±5.10µs	196.1±6.09µs	-1.73%
Array creation (Execution)	3.1±0.07ms	3.1±0.11ms	0.00%
Array creation (Full)	3.5±0.11ms	3.4±0.12ms	+2.94%
Array pop (Execution)	1184.6±67.11µs	1164.3±78.17µs	+1.74%
Array pop (Full)	1481.4±53.50µs	1429.7±30.72µs	+3.62%
Boolean Object Access (Execution)	4.6±0.12µs	4.5±0.13µs	+2.22%
Boolean Object Access (Full)	186.9±4.58µs	186.5±5.42µs	+0.21%
Create Realm	433.1±12.98ns	426.9±12.61ns	+1.45%
Dynamic Object Property Access (Execution)	5.5±0.24µs	5.5±0.23µs	0.00%
Dynamic Object Property Access (Full)	196.0±10.44µs	190.9±5.66µs	+2.67%
Expression (Lexer)	2.3±0.07µs	2.4±0.18µs	-4.17%
Expression (Parser)	5.1±0.14µs	5.1±0.19µs	0.00%
Fibonacci (Execution)	1023.4±37.01µs	1031.4±55.41µs	-0.78%
Fibonacci (Full)	1217.2±41.25µs	1237.8±41.81µs	-1.66%
For loop (Execution)	22.5±1.23µs	22.5±1.77µs	0.00%
For loop (Full)	204.7±8.94µs	203.4±8.80µs	+0.64%
For loop (Lexer)	5.1±0.19µs	5.1±0.17µs	0.00%
For loop (Parser)	14.1±0.37µs	14.5±0.92µs	-2.76%
Goal Symbols (Parser)	8.6±0.41µs	8.2±0.35µs	+4.88%
Hello World (Lexer)	856.2±89.25ns	835.0±47.54ns	+2.54%
Hello World (Parser)	2.2±0.09µs	2.1±0.08µs	+4.76%
Long file (Parser)	6.4±0.26ms	6.3±0.12ms	+1.59%
Number Object Access (Execution)	3.6±0.13µs	3.6±0.11µs	0.00%
Number Object Access (Full)	186.0±9.81µs	187.9±14.21µs	-1.01%
Object Creation (Execution)	4.7±0.26µs	4.7±0.12µs	0.00%
Object Creation (Full)	206.8±7.37µs	218.7±14.93µs	-5.44%
RegExp (Execution)	71.9±1.98µs	72.4±2.69µs	-0.69%
RegExp (Full)	300.7±16.61µs	295.6±9.19µs	+1.73%
RegExp Literal (Execution)	71.6±2.20µs	72.3±2.66µs	-0.97%
RegExp Literal (Full)	269.8±8.15µs	273.8±11.59µs	-1.46%
RegExp Literal Creation (Execution)	68.7±2.81µs	68.4±3.12µs	+0.44%
RegExp Literal Creation (Full)	297.8±7.80µs	296.3±11.96µs	+0.51%
Static Object Property Access (Execution)	5.0±0.24µs	5.0±0.18µs	0.00%
Static Object Property Access (Full)	187.1±11.11µs	195.5±9.02µs	-4.30%
String Object Access (Execution)	6.7±0.19µs	6.8±0.50µs	-1.47%
String Object Access (Full)	190.2±5.67µs	192.0±7.74µs	-0.94%
String comparison (Execution)	6.7±0.36µs	6.3±0.35µs	+6.35%
String comparison (Full)	187.8±6.01µs	188.2±7.58µs	-0.21%
String concatenation (Execution)	5.5±0.28µs	5.1±0.25µs	+7.84%
String concatenation (Full)	182.7±4.54µs	185.5±9.93µs	-1.51%
String copy (Execution)	4.0±0.12µs	3.8±0.13µs	+5.26%
String copy (Full)	179.9±8.44µs	177.6±5.90µs	+1.30%
Symbols (Execution)	3.2±0.10µs	3.3±0.18µs	-3.03%
Symbols (Full)	172.1±5.50µs	172.3±7.72µs	-0.12%

[Lan2u]

Can you add a test that demonstrates the correct behavior when the position argument of lastIndexOf is not a number (default to positive infinity)

[github-actions]

Benchmark for 8a956e0

Click to view benchmark

Test	PR Benchmark	Master Benchmark	%
Arithmetic operations (Execution)	379.5±8.17ns	385.3±10.43ns	-1.51%
Arithmetic operations (Full)	172.2±4.20µs	181.6±27.78µs	-5.18%
Array access (Execution)	8.8±0.18µs	9.0±0.30µs	-2.22%
Array access (Full)	190.7±5.96µs	199.8±14.29µs	-4.55%
Array creation (Execution)	3.4±0.11ms	3.4±0.09ms	0.00%
Array creation (Full)	3.7±0.09ms	3.9±0.22ms	-5.13%
Array pop (Execution)	1194.3±64.93µs	1224.6±16.81µs	-2.47%
Array pop (Full)	1553.7±56.04µs	1569.3±43.90µs	-0.99%
Boolean Object Access (Execution)	4.8±0.28µs	4.8±0.13µs	0.00%
Boolean Object Access (Full)	192.3±18.53µs	186.3±3.68µs	+3.22%
Create Realm	446.6±6.45ns	453.2±16.36ns	-1.46%
Dynamic Object Property Access (Execution)	5.4±0.37µs	5.3±0.06µs	+1.89%
Dynamic Object Property Access (Full)	184.4±12.55µs	188.7±4.89µs	-2.28%
Expression (Lexer)	2.4±0.06µs	2.5±0.36µs	-4.00%
Expression (Parser)	5.6±0.29µs	5.7±0.13µs	-1.75%
Fibonacci (Execution)	987.2±29.59µs	980.4±21.65µs	+0.69%
Fibonacci (Full)	1179.4±24.83µs	1223.1±52.76µs	-3.57%
For loop (Execution)	22.7±0.71µs	23.2±2.27µs	-2.16%
For loop (Full)	202.4±8.96µs	206.0±8.15µs	-1.75%
For loop (Lexer)	5.3±0.12µs	5.4±0.14µs	-1.85%
For loop (Parser)	14.4±0.71µs	14.2±0.44µs	+1.41%
Goal Symbols (Parser)	8.8±0.68µs	8.7±0.43µs	+1.15%
Hello World (Lexer)	828.3±23.56ns	854.4±29.62ns	-3.05%
Hello World (Parser)	2.2±0.06µs	2.3±0.16µs	-4.35%
Long file (Parser)	6.5±0.16ms	6.6±0.13ms	-1.52%
Number Object Access (Execution)	3.7±0.17µs	3.8±0.09µs	-2.63%
Number Object Access (Full)	186.1±11.60µs	185.1±5.05µs	+0.54%
Object Creation (Execution)	4.6±0.15µs	4.6±0.07µs	0.00%
Object Creation (Full)	204.2±5.84µs	208.3±10.03µs	-1.97%
RegExp (Execution)	70.2±2.34µs	70.8±1.41µs	-0.85%
RegExp (Full)	295.2±11.83µs	299.1±11.25µs	-1.30%
RegExp Literal (Execution)	70.0±1.99µs	71.2±2.49µs	-1.69%
RegExp Literal (Full)	260.5±6.16µs	263.8±9.19µs	-1.25%
RegExp Literal Creation (Execution)	67.2±1.99µs	69.9±7.56µs	-3.86%
RegExp Literal Creation (Full)	289.2±6.88µs	292.0±8.70µs	-0.96%
Static Object Property Access (Execution)	4.8±0.16µs	4.8±0.18µs	0.00%
Static Object Property Access (Full)	183.0±4.51µs	188.9±7.95µs	-3.12%
String Object Access (Execution)	6.8±0.15µs	6.9±0.36µs	-1.45%
String Object Access (Full)	185.1±6.92µs	189.1±3.48µs	-2.12%
String comparison (Execution)	6.3±0.15µs	6.2±0.10µs	+1.61%
String comparison (Full)	184.9±8.33µs	188.7±3.93µs	-2.01%
String concatenation (Execution)	5.2±0.31µs	5.1±0.13µs	+1.96%
String concatenation (Full)	178.5±2.13µs	187.8±10.84µs	-4.95%
String copy (Execution)	3.8±0.10µs	3.8±0.06µs	0.00%
String copy (Full)	179.4±7.28µs	179.3±7.86µs	+0.06%
Symbols (Execution)	3.2±0.15µs	3.2±0.18µs	0.00%
Symbols (Full)	169.7±3.37µs	176.5±6.53µs	-3.85%