ANTLR version 4.7.1 is a minor release but with lots of little improvements and bug fixes. You can find the pull requests grouped by target language below. Also, please find below the contributor list (auto-generated from the issues and pull request).

Summary of new features and improvements

• You can now import lexers with modes into other lexer grammars [...]
• The -o and -lib commandline options didn't always do the obvious thing and in fact presented some problems. With clean that up but requires a new -Xexact-output-dir command line option to enable it to avoid breaking tools built on previous versions of ANTLR [...]
• For languages that support case insensitive keywords such as SQL, ANTLR does not have a built-in mechanism. Programmers either specify case insensitive lexers rules directly or they can build a special input stream that presents characters as uppercase to the lexer. I have provided documentation that describes both approaches including sample streams in various targets. [...]
• The Swift runtime was migrated to Swift 4. [...]
• You can generate SVG now from parse trees in Java target. [...]
• The NuGet package now includes the .NET Core DLL and supports both .NET 3.5 and up, as well as .NET Core. [...]

Issues fixed

• Python3 runtime says 4.6 not 4.7 (status:invalid, target:python3)
• Can not generate java files from Rust grammar file (actions, code-gen, type:bug)
• Unexpected code generation location behavior (cross-platform-issue, type:bug)
• Compiling seperate lexer and parser in subdirectory fails (comp:build, status:duplicate, type:bug)

Improvements, features

• Changed rotation to support 32 and 64-bit architectures as noted in issue #2060. (target:go, type:improvement)
• Case insensitivity doc (comp:doc, comp:runtime, lexers, type:improvement)
• Import lexers with modes into other lexer grammars (comp:tool, lexers, type:improvement)
• Add an accessLevel parser option. (actions, type:improvement)
• Support building C++ Runtime with Intel compilers (target:cpp, type:improvement)
• Improve the "gnu" message format (comp:tool, error-handling, type:improvement)
• Security related issue with System.getenv (comp:runtime, type:improvement)
• New unreachable token value warning (comp:tool, error-handling, type:improvement)
• Simplify output path generation; new -Xexact-output-dir option (actions, comp:build, comp:tool, type:improvement)
• Remove ANTLRError.nullPointer from the Swift runtime. (type:improvement)
• Migrate the Swift runtime to Swift 4. (target:swift, type:improvement)
• Report InputMismatchException with original context information (error-handling, target:java, type:improvement)
• Many fixes to antlr4-maven-plugin dependency analysis (comp:build, type:improvement)
• Implemented TokenStreamRewriter (comp:runtime, target:go, type:improvement)
• added SVG export of parse tree (target:java, trees-contexts, type:improvement)
• NuGet packaging for .NET Core (comp:build, target:csharp, type:improvement)
• CPP target runtime: fixed a memleak (target:cpp, type:improvement)
• Support importing multi-mode lexer grammars (comp:runtime, lexers, type:improvement)

Pull requests grouped by target

csharp target

• Add extra diagnostics and a retry to the C# runtime tests and upgrade the macOS runtime (comp:build, comp:testing, target:csharp)
• #2021 fixes nuget packaging options to avoid missing dll exceptions (comp:build, target:csharp)
• fix to the ATN deserialiser issue on big endian architecture (target:csharp)
• for linux target, bring up to jdk8 since jdk7 no longer available for Trusty; for linux and osx targets, bring up dotnet from 1.0.3 to 1.0.4; Trusty image now has mvn 3.3.9 builtin, removed install code (comp:build, target:csharp)
• Set version to 4.7.1 because 4.7.0 already exists on Nuget (target:csharp)
• NuGet packaging for .NET Core (comp:build, target:csharp, type:improvement)
• speed up tests; rename runtime dll ready for nuget (target:csharp)
• update to .netcore v1.0.1; add osx build (comp:build, target:csharp)

cpp target

• The correction for cmake depends on the demo (comp:build, target:cpp)
• Support building C++ Runtime with Intel compilers (target:cpp, type:improvement)
• CMake build fixes for Visual Studio (comp:build, target:cpp)
• CMake build fixes for Visual Studio (comp:build, target:cpp)
• Add MSVC support to c++ cmake build (comp:build, target:cpp)
• Remove the useless visibility attribute from this "enum class" declaration (target:cpp)
• C++ runtime: Fix two issues found by coverity (target:cpp)
• Build fixes after previous C++ patch (comp:build, target:cpp)
• Rework C++ Runtime Interval, IntervalSet, ATN and ATNState (atn-analysis, target:cpp)
• Build fix/correction for UTF32 conversion. (target:cpp)
• Small optimizations (target:cpp)
• C++ runtime changes for high warning levels (target:cpp)
• Fix listener example in C++ documentation. (comp:doc, target:cpp)
• Make ParseTreeWalker::DEFAULT provide an IterativeParseTreeWalker (target:cpp, trees-contexts)
• Fix the utf8 convertor for VS2017 (target:cpp, unicode)
• Update C++ target doc for latest API changes - fixes #1824. (comp:doc, target:cpp)
• Channel parameter in c-tor is now a size_t - fixes #1827. (target:cpp)
• Small fix in cmake file. Fixes #1809. (comp:build, target:cpp)
• CPP target runtime: fixed a memleak (target:cpp, type:improvement)

go target

• Export GetHiddenTokens routines (target:go)
• Fix issue with tree finding when the underlying slice needs to be resized. (target:go)
• Changed rotation to support 32 and 64-bit architectures as noted in issue #2060. (target:go, type:improvement)
• Add RuleContext interface methods to reserved words (target:go)
• Revert "[Go] Interval" (target:go)
• Placed the CommonSetStuff code inside a scope (code-gen, target:go)
• Export Go lexer methods (target:go)
• Allowing Go runtime compilation to succeed under ARM (target:go)
• Add CommonTokenStream test. (target:go)
• Interval (target:go)
• Implemented TokenStreamRewriter (comp:runtime, target:go, type:improvement)
• Add getter method to Interval. (target:go)
• Go file header complies with standardised Go 'generated code' header (code-gen, target:go)
• Fix #1925 (target:go, target:javascript, target:python2, target:python3, unicode)
• Add proper error handling semantics to FileStream. (target:go)

java target

• Fixes #2069 to catch env var security exception (target:java, type:bug)
• Fix codegen error (Java) when a lexer has only fragment tokens (code-gen, target:java)
• Fixed empty CodePointCharStream throwing exception on getText. (target:java, unicode)
• Report InputMismatchException with original context information (error-handling, target:java, type:improvement)
• Avoid adding to closureBusy before all ATNConfig properties are set (atn-analysis, comp:performance, target:java, type:bug)
• added SVG export of parse tree (target:java, trees-contexts, type:improvement)

javascript target

• enable auto-suggest engines by exposing the lexer ATN as a property, similar to the parser ATN (target:javascript)
• Fix Interval usage in ErrorStrategy.js (target:javascript)
• Require superClass for Lexer in split mode for JavaScript target (target:javascript)
• fix inconsistent naming in target stg (target:javascript)
• Fix #1925 (target:go, target:javascript, target:python2, target:python3, unicode)
• Add new keyword to return proper InputStreams (target:javascript, type:bug)

python2,3 targets

• fix #2031 (target:python2)
• Python: add public getter to parsers to access syntax error count. (target:python2, target:python3)
• Fix #1925 (target:go, target:javascript, target:python2, target:python3, unicode)
• Fix input mismatch errors not reported the same way as Java in Python (comp:testing, error-handling, target:python2, target:python3)
• Use spaces consistently to indent the generated Python code. (target:python2, target:python3)
• Import RuleContext into the antlr4 module namespace. See Issue #2012. (target:python3)
• Python 3 codegen probably didn't mean to limit ATN segment size to 2 XOR 31 (target:python3, type:bug)

swift target

• Fix parse-cancellation in BailErrorStrategy. (target:swift)
• Remove Recognizer.tokenTypeMapCache and .ruleIndexMapCache. (target:swift)
• Fix initialization of {Lexer,Parser}Interpreter.decisionToDFA. (target:swift)
• Remove Triple.swift. (target:swift)
• Make ATNSimulator.sharedContextCache non-optional. (target:swift)
• Remove unused ATN.modeNameToStartState. (target:swift)
• Some minor tidyups. (target:swift)
• Make DFA.precedenceDfa be a "let" rather than a "var". (target:swift)
• Replace IntervalSet.setReadonly with makeReadonly. (target:swift)
• Make all the mutexes "let" rather than "var". (target:swift)
• Tidy-ups inside the Swift runtime around ParseTree, ParserRuleContext (target:swift)
• Remove use of deprecated String functions (target:swift)
• Open the error strategies to subclasses. (target:swift)
• Tidy ATNDeserializer. (target:swift)
• Report errors in ANTLRFileStream. (target:swift)
• Implement UUID.init(mostSigBits, leastSigBits) in the Swift runtime. (target:swift)
• Fix ParseTreePatternMatcher.split in the Swift runtime. (target:swift)
• Make CharStream.init(CharStream) required (in the Swift runtime). (target:swift)
• Fix UnbufferedCharStream in the Swift runtime. (target:swift)
• Fix retain cycles in the Swift runtime (target:swift)
• Implement UnbufferedCharStream in the Swift runtime. (target:swift)
• Tidy up the exception behavior around IntervalSet and ATNConfigSet. (target:swift)
• Tidy up the exception handling around RecognitionException. (target:swift)
• Tidyups inside the Swift runtime (target:swift)
• Update boot.py and swift-target.md to reflect Swift 4 migration changes. (target:swift)
• Improve MurmurHash (target:swift)
• Migrate the Swift runtime to Swift 4. (target:swift, type:improvement)
• Updated swift-target.md. (comp:doc, target:swift)
• Swift Documentations (comp:doc, target:swift)
• Swift Target Linux Support (target:swift)
• Supporting Script for Swift Runtime (target:swift)
• Fixing Problems after Swift3.1 Release (target:swift)
• Fixing Xcode project setting. (comp:build, target:swift)
• Obsolete String.contains(_:) of Swift runtime (target:swift)

Contributors

• 42 items: Ewan Mellor (ewanmellor)
• 8 items: Terence Parr (parrt)
• 8 items: Mike Lischke (mike-lischke)
• 7 items: hanjoes (hanjoes)
• 5 items: ericvergnaud
• 4 items: David Sisson (davesisson)
• 4 items: Maxim (gendalph)
• 4 items: Sam Harwell (sharwell)
• 3 items: Corey Kosak (kosak)
• 3 items: Dong Xie (xied75)
• 2 items: JavaDDD
• 2 items: Ivan Kochurkin (KvanTTT)
• 2 items: Andrew Brampton (bramp)
• 2 items: Sachin Jain (sachinjain024)
• 2 items: shirou (shirou)
• 2 items: Arshinskiy Mike (neatnerd)
• 2 items: Matt Hauck (matthauck)
• 2 items: Renáta Hodován (renatahodovan)
• 2 items: jm-mikkelsen
• 2 items: lys0716
• 1 items: Oran Epelbaum (oranoran)
• 1 items: Nicolas Croad (niccroad)
• 1 items: zqlu (zqlu)
• 1 items: Ajay Panyala (ajaypanyala)
• 1 items: Jason Mooberry (jasonmoo)
• 1 items: simkimsia
• 1 items: Rostislav Listerenko (kaedvann)
• 1 items: fallnirvana (moon-fall)
• 1 items: Robert Jacobson (rljacobson)
• 1 items: Bráulio Bezerra (brauliobz)
• 1 items: Masashi Fujita (objectx)
• 1 items: Sandy Corn (onekosha)
• 1 items: Eddy Reyes (ereyes01)
• 1 items: Milan Aleksić (milanaleksic)
• 1 items: Tiago Mazzutti (tiagomazzutti)
• 1 items: Niels Basjes (nielsbasjes)
• 1 items: Venkat Peri (venkatperi)
• 1 items: Vaibhav Vaingankar (vaibhavaingankar09)
• 1 items: Maurice van der Pot (Griffon26)
• 1 items: Dan Halperin (dhalperi)
• 1 items: Sergey Parshukov (jBugman)
• 1 items: alim (alimg)
• 1 items: rlfnb
• 1 items: Daniel Katz (danielkatz)
• 1 items: Erik A. Brandstadmoen (erikbra)
• 1 items: Will Fuqua (waf)
• 1 items: Jim Allman (jimallman)
• 1 items: Shravan Narayan (shravanrn)
• 1 items: Brad Hards (bradh)
• 1 items: Floor (FloorGoddijn)
• 1 items: Ben Hamilton (Ben Gertzfield) (bhamiltoncx)
• 1 items: Jonas Auer (cmd-johnson)
• 1 items: Gerald Rosenberg (grosenberg)
• 1 items: Arthur Fabre (arthurfabre)