[kjw142857]

This PR expands on #89 to enhance narrowing typecasts as well as fixing some known limitations.

Changes:

• Byte, short and char now are able to be narrowcasted using the Java 8 typecasting rules
• Fixed a grammar rule which was causing errors when performing a non-primitive (reference) narrrowing typecast.
• Fixed a bug where narrowing typecasts rounded numbers (e.g. double to int) instead of truncating them.
• Fixed a bug which allowed compilation of illegal binary operations between disallowed types.
• Fixed a bug where an extra line would be printed after every print statment.
• Fixed a bug where some primitive types would not be printed correctly.
• Fixed a bug where break in a switch statement in a loop would break the loop instead of the switch.
• Fixed a bug where instantiation of abstract classes succeeding in compiling, and added checks that all abstract methods in an abstract class are eventually implemented by its descendant concrete classes.
• Fixed a bug where field access to a parent class using the super keyword could not compile.
• Fixed a bug where calling an inherited method could not compile.
• Fixed a bug where field initialisation of arrays could not compile.
• Fixed a bug where inheritance from an imported library discarded the details of the import.
• Fixed a bug where a bare this keyword could not be parsed.
• Fixed an issue with checked exceptions and added support for throwing user-defined exceptions.
• Fixed a bug where arrays could not be initialised with default values.
• Fixed a bug where arrays could not be initialised with an explicit type definition.

[github-actions]

Coverage report

St.❔	Category	Percentage	Covered / Total
🟡	Statements	76.59% (+4.79% 🔼)	10575/13808
🟡	Branches	65.17% (+4.87% 🔼)	3665/5624
🟡	Functions	75.75% (+5.43% 🔼)	1902/2511
🟡	Lines	77.49% (+4.78% 🔼)	9853/12716

Show new covered files 🐣

St.❔	File	Statements	Branches	Functions	Lines
🟢	... / StrictMath.ts	100%	100%	100%	100%
🟡	jvm/utils/fdlibm.ts	71.9%	43.09%	100%	74.77%
🟢	... / Double.ts	100%	100%	100%	100%
🟢	... / Float.ts	100%	100%	100%	100%
🟢	... / castExpression.test.ts	100%	100%	100%	100%
🟢	... / literals.test.ts	100%	100%	100%	100%
🟢	... / switch.test.ts	100%	100%	100%	100%
🟢	... / inheritance.test.ts	100%	100%	100%	100%
🟢	... / throw.test.ts	100%	100%	100%	100%

Show files with reduced coverage 🔻

St.❔	File	Statements	Branches	Functions	Lines
🔴	... / references.ts	58.42% (-0.09% 🔻)	41.96%	68%	58.68% (-0.09% 🔻)
🟢	... / compiler.ts	98.57% (-0.35% 🔻)	88.75% (+8.19% 🔼)	100%	98.96% (+0.11% 🔼)
🟢	... / constant-pool-manager.ts	98.86% (+0.15% 🔼)	91.67% (-2.78% 🔻)	96.77% (+0.22% 🔼)	98.85% (+0.15% 🔼)

Test suite run success

2310 tests passing in 78 suites.

Report generated by 🧪jest coverage report action from f8a93bf