[CS2] 2.0.0-beta5

[GeoffreyBooth]

In this PR itself (see updated docs):

• The docs are updated to use Bootstrap 4 beta, including refactoring a lot of our styles.
• CodeMirror is updated to 5.29.0, which works on mobile.
• “Try CoffeeScript” has been refactored to work on mobile, and a link to it has been added to the mobile nav.
• Fix [CS2] Docs: Erroneous statement in "unsupported named functions" section #4642, removed erroneous statement about named functions.

And this rolls up all the following fixes:

• Fix async tests ([CS2] Fix async tests #4680)
• Don’t require async/await support to run coffee ([CS2] Don’t require async/await support to run coffee #4679)
• Fix Lexer: a = ; 5: Suppressed newline should be unsuppressed by semicolon #3098: Suppressed newline should be unsuppressed by semicolon ([CS2] Fix #3098: Suppressed newline should be unsuppressed by semicolon #4669)
• Use _extends utility instead of Object.assign() for object spreads ([CS2] use _extends utility instead of Object.assign() for object spreads #4675)
• Fix [CS2] object spread destructuring bug #4651: object spread destructuring bug ([CS2] Fix #4651: object spread destructuring bug #4652)
• Fix v3 source map ([CS2] Fix v3 source map #4671)
• Fix Lexer: Spaces after :: cause unexpected results #1768: Ignore space after :: ([CS2] Fix #1768: Ignore space after :: #4670)
• Refine [CS2] add parens to chained do IIFE #4666: add parens to chained do IIFE with params ([CS2] Refine #4666: add parens to chained do IIFE with params #4672)
• Add parens to chained do IIFE ([CS2] add parens to chained do IIFE #4666)
• Fix Lexer: Breaking change in multiple row function chaining #4576: Allow accessing a property of a function literal (like .call) via chaining syntax ([CS2] Allow chained access of a property of a function literal #4665)
• Fix [CS2] Quotation mark characters are escaped unnecessarily in template literals #4589: Unquote all interpolated strings, not just CSX ones, so that quotation marks are not unnecessarily escaped in backtick-delimited strings/template literals ([CS2] Fix #4589: Don’t unnecessarily escape quotes in template literals #4660)
• Fix Invalid JS: [a?.b…] compiles to invalid JavaScript #4260 and Invalid JS: Splatted statement causes if block inside array element #1349: Splat error with soak properties or expressions ([CS2] Fix #4260 and #1349: Splat error with soak properties or expressions #4644)
• Fix Invalid JS: Compiler emits invalid JS when throw followed by if or for #3709, Invalid JS: Nested throw expressions #3789: throw an if, for, switch, while ([CS2] Fix #3709, #3789: ‘throw’ an ‘if’, ‘for’, ‘switch’, ‘while’ #4664)
• Fix Lexer: Input of asterisk (*) throws exception #4575: Check for the previous token’s existence before comparing against it ([CS2] Fix #4575: Leading asterisk #4663)
• Fix CLI: Allow user to set output filename #2870: Allow specifying output filename ([CS2] Fix #2870: Allow specifying output filename #4661)
• Fix Lexer: Input of colon (:) throws exception #4578: Never look back past the start of the token stream ([CS2] Fix #4578: Leading colon shouldn’t throw exception #4662)
• Fix [CS2] Rewriter: Inline block comments in CSX not getting output #4629: interpolations (whether in strings or CSX tags) with only comments ([CS2] Fix #4629: interpolations (whether in strings or CSX tags) with only comments #4659)
• Fix CLI: --require options doesn't work for file with illegal chars for JS variable #4209: --require for filenames that are invalid identifiers ([CS2] Fix #4209: --require for filenames that are invalid identifiers #4658)
• Fix CLI: Line numbers shown as NaN in stack trace when compiling CoffeeScript inside CoffeeScript #4558: Stack trace line numbers for scripts that compile CoffeeScript (Fix #4558: Stack trace line numbers for scripts that compile CoffeeScript #4645)
• Docs: Define functions used in loop examples (Docs: Define functions used in loop examples #4653)
• Fix object spread destructuring bug ([CS2] object spread destructuring bug #4651)
• Fix [CS2] Lexer/Nodes: Expansion that becomes rest parameter causes runtime error #4631: Expansion that becomes rest parameter causes runtime error ([CS2] Fix #4631: Expansion that becomes rest parameter causes runtime error #4634)
• Fix [CS2] Nodes: Missing declarations for generated variables in parameter defaults #4413: Generated variables in function parameters ([CS2] Fix #4413: Generated variables in function parameters #4640)

There’s one more PR pending:

• Fix Lexer: Backticks should allow adding code to class body #4464: backticked expressions in class body (Fix #4464: backticked expressions in class body #4668)

@connec or @lydell do either of you have a moment to review that one to hopefully slip it into this release? Otherwise it can catch the next train.

[lydell]

As always, a superb job summarizing all that’s happened since the last release! 👍

Regarding #4668, it feels like @connec is the one who knows the most about classes, so I’ll defer to him.