• cmd/shfmt
  • Report the correct language variant in parser error messages - #1102
  • Move --filename out of the parser options category - #1079
• syntax
  • Parse all CRLF line endings as LF, including inside heredocs - #1088
  • Count skipped backslashes inside backticks in position column numbers - #1098
  • Count skipped null bytes in position column numbers for consistency
• interp
  • Fix a regression in v3.9.0 which broke redirecting files to stdin - #1099
  • Fix a regression in v3.9.0 where HandlerContext.Stdin was never nil
  • Add an Interactive option to be used by interactive shells - #1100
  • Support closing stdin, stdout, and stderr via redirections like <&-

Consider becoming a sponsor if you benefit from the work that went into this release!

This release drops support for Go 1.21 and includes many fixes.

• cmd/shfmt
  • Switch the diff implementation to remove one dependency
• syntax
  • Protect against overflows in position offset integers
• interp
  • Use os.Pipe for stdin to prevent draining by subprocesses - #1085
  • Support cancelling reads in builtins when stdin is a file - #1066
  • Support the nocaseglob bash option - #1073
  • Support the Bash 5.2 @k parameter expansion operator
  • Support the test -O and test -G operators on non-Windows - #1080
  • Support the read -s builtin flag - #1063
• expand
  • Add support for case insensitive globbing - #1073
  • Don't panic when pattern words are nil - #1076

A special thanks to @theclapp for their contributors to this release!

Consider becoming a sponsor if you benefit from the work that went into this release!

This release drops support for Go 1.19 and 1.20 and includes many features and bugfixes, such as improving EditorConfig support in shfmt.

• cmd/shfmt
  • Support EditorConfig language sections such as [[shell]] - #664
  • Add --apply-ignore for tools and editors - #1037
• syntax
  • Allow formatting redirects before all command argumetnts - #942
  • Support brace expansions with uppercase letters - #1042
  • Unescape backquotes in single quotes within backquotes - #1041
  • Better error when using function in POSIX mode - #993
  • Better column numbers for escapes inside backquotes - #1028
• interp
  • Support parentheses in classic test commands - #1036
  • Determine access to a directory via unix.Access - #1033
  • Support subshells with FuncEnviron as Env - #1043
  • Add support for fs.DirEntry via ReadDirHandler2
• expand
  • Add support for fs.DirEntry via ReadDir2
  • Support zero-padding in brace expansions - #1042

• syntax
  • Correctly parse $foo#bar as a single word - #1003
  • Make &> redirect operators an error in POSIX mode - #991
  • Avoid producing invalid shell when minifying some heredocs - #923
  • Revert the simplification of ${foo:-} into ${foo-} - #970
• interp
  • Add ExecHandlers to support layering multiple middlewares - #964
  • Add initial support for the select clause - #969
  • Support combining the errexit and pipefail options - #870
  • Set EUID just like UID - #958
  • Replace panics on unimplemented builtins with errors - #999
  • Tweak build tags to support building for js/wasm - #983
• syntax/typedjson
  • Avoid reflect.Value.MethodByName to reduce binary sizes - #961

This release drops support for Go 1.17 and includes many features and fixes.

• cmd/shfmt
  • Implement --from-json as the reverse of --to-json - #900
  • Improve the quality of the --to-json output - #900
  • Provide detected language when erroring with -ln=auto - #803
• syntax
  • Don't require peeking two bytes after echo * - #835
  • Simplify ${name:-} to the equivalent ${name-} - #849
  • Don't print trailing whitespaces on nested subshells - #814
  • Don't print extra newlines in some case clauses - #779
  • Don't indent comments preceding case clause items - #917
  • Allow escaped newlines before unquoted words again - #873
  • Parse a redirections edge case without spaces - #879
  • Give a helpful error when <<< is used in POSIX mode - #881
  • Forbid ${!foo*} and ${!foo@} in mksh mode - #929
  • Batch allocations less aggressively in the parser
• syntax/typedjson
  • Expose --from-json and --to-json as Go APIs - #885
• expand
  • Improve support for expanding array keys and values - #884
  • Don't panic on unsupported syntax nodes - #841
  • Don't panic on division by zero - #892
  • Properly expand unquoted parameters with spaces - #886
  • Trim spaces when converting strings to integers - #928
• interp
  • Add initial implementation for mapfile and readarray - #863
  • Improve matching patterns against multiple lines - #866
  • Support %b in the printf builtin - #955
  • Display all Bash options in shopt - #877
• pattern
  • Add EntireString to match the entire string using ^$ - #866

• cmd/shfmt
  • Fix the Docker publishing script bug which broke 3.5.0 - #860
• interp
  • Support multi-line strings when pattern matching in [[ - #861
  • Invalid glob words are no longer removed with nullglob - #862
• pattern
  • Regexp now returns the typed error SyntaxError - #862

This release drops support for Go 1.16 and includes many new features.

• cmd/shfmt
  • Switch to -ln=auto by default to detect the shell language
  • Add support for long flags, like --indent for -i
• syntax
  • Allow extglob wildcards as function names like @() { ... }
  • Add support for heredocs surrounded by backquotes
  • Add support for backquoted inline comments
  • Add NewPos to create Pos values externally
  • Support escaped newlines with CRLF line endings
  • Minify no longer omits a leading shebang comment
  • Avoid printing escaped newlines in non-quoted words
  • Fix some printer edge cases where comments weren't properly spaced
• fileutil
  • Add Shebang to extract the shell language from a #! line
• expand
  • Reimplement globstar ** globbing for correctness
  • Replace os.Stat as the last direct use of the filesystem
• interp
  • Add CallHandler to intercept all interpreted CallExpr nodes
  • Add ReadDirHandler to intercept glob expansion filesystem reads
  • Add StatHandler to intercept os.Stat and os.Lstat calls
  • Always surface exit codes from command substitutions
  • Add initial and incomplete support for set -x
  • Add support for cd - as cd "$OLDPWD"
  • Avoid panic on set - args

• cmd/shfmt
  • New Docker v3 tag to track the latest stable version
  • Don't duplicate errors when walking directories
• interp
  • Properly handle empty paths in the test builtin
  • Allow unsetting global vars from inside a function again
  • Use %w to wrap errors in Dir

• The tests no longer assume what locales are installed
• interp
  • Keep PATH list separators OS-specific to fix a recent regression
  • Avoid negative elapsed durations in the time builtin

• syntax
  • Don't return an empty string on empty input to Quote
• expand
  • Properly sort in ListEnviron to avoid common prefix issues
• interp
  • export used in functions now affects the global scope
  • Support looking for scripts in $PATH in source
  • Properly slice arrays in parameter expansions

This release drops support for Go 1.15, which allows the code to start benefitting from io/fs.

• cmd/shfmt
  • Walks directories ~10% faster thanks to filepath.WalkDir
• syntax
  • Add Quote to mirror strconv.Quote for shell syntax
  • Skip null characters when parsing, just like Bash
  • Rewrite fuzzers with Go 1.18's native fuzzing
• fileutil
  • Add CouldBeScript2 using io/fs.DirEntry
• expand
  • Skip or stop at null characters, just like Bash
• interp
  • Set GID just like UID
  • Add support for read -p
  • Add support for pwd flags
  • Create random FIFOs for process substitutions more robustly
  • Avoid leaking an open file when interpreting $(<file)

• syntax
  • Don't convert & in a separate line into ;
  • Fix a BinaryNextLine edge case idempotency bug
  • Never start printing a command with an escaped newline
• interp
  • Support calling Runner.Reset before Runner.Run
  • Obey set -e for failed redirections

• cmd/shfmt
  • Document the FORCE_COLOR env var to always use colors in diffs
• syntax
  • Add the printer SingleLine option to avoid printing newlines
  • Positions now use more bits for line numbers than column numbers
  • Test operators like && and || no longer escape newlines
  • Properly handle closing backquotes in a few edge cases
  • Properly handle trailing escaped newlines in heredocs
• interp
  • Redesigned variable scoping to fix a number of edge cases
  • Refactor set -o nounset support to fix many edge cases
  • Deprecate LookPath in favor of LookPathDir
  • Array element words are now expanded correctly
  • Add support for trap with error and exit signals
  • Add support for shopt -s nullglob
  • Add support for type -p

• cmd/shfmt
  • Don't stop handling arguments when one results in a failure
• expand
  • Don't panic when a backslash is followed by EOF

• syntax
  • Avoid comment position panic in the printer

• syntax
  • Fix an endless loop when parsing single quotes in parameter expansions
  • Properly print assignments using escaped newlines
  • Print inline heredoc comments in the right place
• interp
  • Always expand ~ in Bash test expressions
• expand
  • Don't panic on out of bounds array index expansions

• cmd/shfmt
  • Add a man page via scdoc; see shfmt.1.scd
  • Add -filename to give a name to standard input
• syntax
  • Add initial support for Bats
  • Protect line and column position numbers against overflows
  • Rewrite arithmetic parsing to fix operator precedence
  • Don't add parentheses to function f {...} declarations for ksh support
  • KeepPadding now obeys extra indentation when using space indentation
  • Properly tokenize (( within test expressions
  • Properly tokenize single quotes within parameter expansions
  • Obey print options inside <<- heredocs
  • Don't simplify indexed parameter expansions in arithmetic expressions
  • Improve parsing errors for missing test expressions
  • LangVariant now implements flag.Value
• interp
  • Avoid panic on C-style loops which omit expressions
  • $@ and $* always exist, so "$@" can expand to zero words

• syntax
  • Fix brace indentation when using FunctionNextLine
  • Support indirect parameter expansions with transformations
  • Stop heredoc bodies only when the entire line matches
• interp
  • Make the tests pass on 32-bit platforms

• cmd/shfmt
  • Recognise function_next_line in EditorConfig files
• syntax
  • Don't ignore escaped newlines at the end of heredoc bodies
  • Improve support for parsing regexes in test expressions
  • Count columns for KeepPadding in bytes, to better support unicode
  • Never let KeepPadding add spaces right after indentation
• interp
  • Hide unset variables when executing programs

• Redesigned Docker images, including buildx and an Alpine variant
• cmd/shfmt
  • Replace source files atomically when possible
  • Support ignore = true in an EditorConfig to skip directories
  • Add -fn to place function opening braces on the next line
  • Improve behavior of -f when given non-directories
  • Docker images and go get installs now embed good version information
• syntax
  • Add support for nested here-documents
  • Allow parsing for loops with braces, present in mksh and Bash
  • Expand CaseClause to describe its in token
  • Allow empty lines in Bash arrays in the printer
  • Support disabling KeepPadding
  • Avoid mis-printing some programs involving &
• interp
  • Add initial support for Bash process substitutions
  • Add initial support for aliases
  • Fix an edge case where the status code would not be reset
  • The exit status code can now reflect being stopped by a signal
  • test -t now uses the interpreter's stdin/stdout/stderr files
• expand
  • Improve the interaction of @ and * with quotes and IFS

• syntax
  • Don't indent after escaped newlines in heredocs
  • Don't parse *[i]=x as a valid assignment
• interp
  • Prevent subshells from defining funcs in the parent shells
• expand
  • Parameters to Fields no longer get braces expanded in-place

• cmd/shfmt
  • Fix an edge case where walking directories could panic
• syntax
  • Only do a trailing read in Parser.Stmts if we have open heredocs
  • Ensure comments are never folded into heredocs
  • Properly tokenize ) after a =~ test regexp
  • Stop parsing a comment at an escaped newline
• expand
  • "$@" now expands to zero fields when there are zero parameters

This is the first stable release as a proper module, now under mvdan.cc/sh/v3/.... Go 1.12 or later is supported.

A large number of changes have been done since the last feature release a year ago. All users are encouraged to update. Below are the major highlights.

• cmd/shfmt
  • Support for EditorConfig files
  • Drop the dependency on diff for the -d flag, now using pure Go
• syntax
  • Overhaul escaped newlines, now represented as WordPart positions
  • Improve some operator type names, to consistently convey meaning
  • Completely remove StmtList
  • Redesign IfClause, making its "else" another IfClause node
  • Redesign DeclClause to remove its broken Opts field
  • Brace expression parsing is now done with a BraceExp word part
  • Improve comment alignment in Printer via a post-process step
  • Add support for the ~ bitwise negation operator
  • Record the use of deprecated tokens in the syntax tree
• interp
  • Improve the module API as "handlers", to reduce confusion with Go modules
  • Split LookPath out of ExecHandler to allow custom behavior
  • Run now returns nil instead of ShellExitStatus(0)
  • OpenDevImpls is removed; see ExampleOpenHandler for an alternative
• expand
  • Redesign Variable to reduce allocations
  • Add support for more escape sequences
  • Make Config a bit more powerful via func fields
  • Rework brace expansion via the new BraceExp word part
• pattern
  • New package for shell pattern matching, extracted from syntax
  • Add support for multiple modes, including filenames and braces

Special thanks to Konstantin Kulikov for his contribution to this release.

• syntax
  • Support array elements without values, like declare -A x=([index]=)
  • Parse for i; do ... uniquely, as it's short for for i in "$@"
  • Add missing error on unclosed nested backquotes
• expand
  • Don't expand tildes twice, fixing echo ~ on Windows
• interp
  • Fix the use of Params as an option to New
  • Support lowercase Windows volume names in $PATH

• expand
  • Support globs with path prefixes and suffixes, like ./foo/*/
  • Don't error when skipping non-directories in glob walks

• syntax
  • Avoid premature reads in Parser.Interactive when parsing Unicode bytes
  • Fix parsing of certain Bash test expression involving newlines
  • Redirect.End now takes the Hdoc field into account
  • ValidName now returns false for an empty string
• expand
  • Environment variables on Windows are case insensitive again
• interp
  • Don't crash on declare $unset=foo
  • Fix a regression where executed programs would receive a broken environment

Note that the published Docker image was changed to set shfmt as the entrypoint, so previous uses with arguments like docker run mvdan/shfmt:v2.6.1 shfmt --version should now be docker run mvdan/shfmt:v2.6.2 --version.

• syntax
  • Fix Parser.Incomplete with some incomplete literals
  • Fix parsing of Bash regex tests in some edge cases
• interp
  • Add support for $(<file) special command substitutions

This is the biggest v2 release to date. It's now possible to write an interactive shell, and it's easier and safer to perform shell expansions.

This will be the last major v2 version, to allow converting the project to a Go module in v3.

• Go 1.10 or later required to build
• syntax
  • Add Parser.Interactive to implement an interactive shell
  • Add Parser.Document to parse a single here-document body
  • Add Parser.Words to incrementally parse separate words
  • Add the Word.Lit helper method
  • Support custom indentation in <<- heredoc bodies
• interp
  • Stabilize API and add some examples
  • Introduce a constructor, and redesign Runner.Reset
  • Move the context from a field to function parameters
  • Remove Runner.Stmt in favor of Run with ShellExitStatus
• shell
  • Stabilize API and add some examples
  • Add Expand, as a more powerful os.Expand
  • Add Fields, similar to the old Runner.Fields
  • Source* functions now take a context
  • Source* functions no longer try to sandbox
• expand
  • New package, split from interp
  • Allows performing shell expansions in a controlled way
  • Redesigned Environ and Variable moved from interp

• syntax
  • Fix a regression where semicolons would disappear within switch cases

• syntax
  • Add support for Bash's {varname}< redirects
  • Add SpaceRedirects to format redirects like > word
  • Parse $\" correctly within double quotes
  • A few fixes where minification would break programs
  • Printing of heredocs within <() no longer breaks them
  • Printing of single statements no longer adds empty lines
  • Error on invalid parameter names like ${1a}
• interp
  • Runner.Dir is now always an absolute path
• shell
  • Expand now supports expanding a lone ~
  • Expand and SourceNode now have default timeouts
• cmd/shfmt
  • Add -sr to print spaces after redirect operators
  • Don't skip empty string values in -tojson
  • Include comment positions in -tojson

• Publish as a JS package, mvdan-sh
• syntax
  • Add DebugPrint to pretty-print a syntax tree
  • Fix comment parsing and printing in some edge cases
  • Indent <<- heredoc bodies if indenting with tabs
  • Add support for nested backquotes
  • Relax parser to allow quotes in arithmetic expressions
  • Don't rewrite declare foo= into declare foo
• interp
  • Add support for shopt -s globstar
  • Replace Runner.Env with an interface
• shell
  • Add Expand as a fully featured version of os.Expand
• cmd/shfmt
  • Set appropriate exit status when -d is used

• syntax
  • Case clause patterns are no longer forced on a single line
  • Add ExpandBraces, to perform Bash brace expansion on words
  • Improve the handling of backslashes within backquotes
  • Improve the parsing of Bash test regexes
• interp
  • Support $DIRSTACK, ${param[@]#word}, and ${param,word}
• cmd/shfmt
  • Add -d, to display diffs when formatting differs
  • Promote -exp.tojson to -tojson
  • Add Pos and End fields to nodes in -tojson
  • Inline StmtList fields to simplify the -tojson output
  • Support -l on standard input

• syntax
  • Don't error on ${1:-default}
  • Allow single quotes in ${x['str key']} as well as double quotes
  • Add support for ${!foo[@]}
  • Don't simplify foo[$x] to foo[x], to not break string indexes
  • Fix Stmt.End when the end token is the background operator &
  • Never apply the negation operator ! to && and || lists
  • Apply the background operator & to entire && and || lists
  • Fix StopAt when the stop string is at the beginning of the source
  • In N>word, check that N is a valid numeric literal
  • Fix a couple of crashers found via fuzzing
• cmd/shfmt
  • Don't error if non-bash files can't be written to

• Tests on Mac and Windows are now ran as part of CI
• syntax
  • Add StopAt to stop lexing at a custom arbitrary token
  • Add TranslatePattern and QuotePattern for pattern matching
  • Minification support added to the printer - see Minify
  • Add ParamExp.Names to represent ${!prefix*}
  • Add TimeClause.PosixFormat for its -p flag
  • Fix parsing of assignment values containing =
  • Fix parsing of parameter expansions followed by a backslash
  • Fix quotes in parameter expansion operators like ${v:-'def'}
  • Fix parsing of negated declare attributes like declare +x name
  • Fix parsing of ${#@}
  • Reject bad parameter expansion operators like ${v@WRONG}
  • Reject inline array variables like a=(b c) prog
  • Reject indexing of special vars like ${1[3]}
  • Reject ${!name} when in POSIX mode
  • Reject multiple parameter expansion actions like ${#v:-def}
• interp
  • Add Bash brace expansion support, including {a,b} and {x..y}
  • Pattern matching actions are more correct and precise
  • Exported some Runner internals, including Vars and Funcs
  • Use the interpreter's $PATH to find binaries
  • Roll our own globbing to use our own pattern matching code
  • Support the getopts sh builtin
  • Support the read bash builtin
  • Numerous changes to improve Windows support
• shell
  • New experimental package with high-level utility functions
  • Add SourceFile to get the variables declared in a script
  • Add SourceNode as a lower-level version of the above
• cmd/shfmt
  • Add -mn, which minifies programs via syntax.Minify

• syntax
  • Add Stmts, to parse one statement at a time
  • Walk no longer ignores comments
  • Parameter expansion end fixes, such as $foo.bar
  • Whitespace alignment can now be kept - see KeepPadding
  • Introduce an internal newline token to simplify the parser
  • Fix Block.Pos to actually return the start position
  • Fix mishandling of inline comments in two edge cases
• interp
  • Expose Fields to expand words into strings
  • First configurable modules - cmds and files
  • Add support for the new TimeClause
  • Add support for namerefs and readonly vars
  • Add support for associative arrays (maps)
  • More sh builtins: exec return
  • More bash builtins: command pushd popd dirs
  • More test operators: -b -c -t -o
  • Configurable kill handling - see KillTimeout
• cmd/shfmt
  • Add -f to just list all the shell files found
  • Add -kp to keep the column offsets in place
• cmd/gosh
  • Now supports a basic interactive mode

• The package import paths were moved to mvdan.cc/sh/...
• syntax
  • Parser and Printer structs introduced with functional options
  • Node positions are now independent - Position merged into Pos
  • All comments are now attached to nodes
  • Support mksh - MirBSD's Korn Shell, used in Android
  • Various changes to the AST:
    • EvalClause removed; eval is no longer parsed as a keyword
    • Add support for Bash's time and select
    • Merge UntilClause into WhileClause
    • Moved Stmt.Assigns to CallExpr.Assigns
    • Remove Elif - chain IfClause nodes instead
  • Support for indexed assignments like a[i]=b
  • Allow expansions in arithmetic expressions again
  • Unclosed heredocs now produce an error
  • Binary ops are kept in the same line - see BinaryNextLine
  • Switch cases are not indented by default - see SwitchCaseIndent
• cmd/shfmt
  • Add -s, which simplifies programs via syntax.Simplify
  • Add -ln <lang>, like -ln mksh
  • Add -bn to put binary ops in the next line, like in v1
  • Add -ci to indent switch cases, like in v1
• interp
  • Some progress made, though still experimental
  • Most of POSIX done - some builtins remain to be done

• syntax
  • Fix parsing of ${foo[$bar]}
  • Fix printer regression where > >(foo) would be turned into >>(foo)
  • Break comment alignment on any line without a comment, fixing formatting issues
  • Error on keywords like fi and done used as commands

• syntax
  • Fix backslashes in backquote command substitutions
  • Disallow some test expressions like [[ a == ! b ]]
  • Disallow some parameter expansions like ${$foo}
  • Disallow some arithmetic expressions like ((1=3)) and (($(echo 1 + 2)))
  • Binary commands like &&, || and pipes are now left-associative
• fileutil
  • CouldBeScript may now return true on non-regular files such as symlinks
• interp
  • New experimental package to interpret a syntax.File in pure Go

• syntax
  • Add support for escaped characters in bash regular expressions
• fileutil
  • New package with some code moved from cmd/shfmt, now importable
  • New funcs HasShebang and CouldBeScript
  • Require shebangs to end with whitespace to reject #!/bin/shfoo

• syntax
  • Parse [[ a = b ]] like [[ a == b ]], deprecating TsAssgn in favour of TsEqual
  • Add support for the -k, -G, -O and -N unary operators inside [[ ]]
  • Add proper support for ! in parameter expansions, like ${!foo}
  • Fix a couple of crashes found via fuzzing
• cmd/shfmt
  • Rewrite [[ a = b ]] into the saner [[ a == b ]] (see above)

• syntax
  • Stable release, API now frozen
  • Parse now reads input in chunks of 1KiB
• cmd/shfmt
  • Add -version flag

• syntax
  • Parse now takes an io.Reader instead of []byte
  • Invalid UTF-8 is now reported as an error
  • Remove backtracking for $(( and ((
  • Walk now takes a func literal to simplify its use

• cmd/shfmt
  • Remove -cpuprofile
  • Don't read entire files into memory to check for a shebang
• syntax
  • Use uint32 for tokens and positions in nodes
  • Use Word and Lit pointers consistently instead of values
  • Ensure Word.Parts is never empty
  • Add support for expressions in array indexing and parameter expansion slicing

• Merge parser, ast, token and printer into a single package syntax
• Use separate operator types in nodes rather than Token
• Use operator value names that express their function
• Keep ; if on a separate line when formatting
• cmd/shfmt
  • Allow whitespace after #! in a shebang
• syntax
  • Implement operator precedence for [[ ]]
  • Parse $(foo) and foo as the same (shfmt then converts the latter to the former)
  • Rename Quoted to DblQuoted for clarity
  • Split ((foo)) nodes as their own type, ArithmCmd
  • Add support for bash parameter expansion slicing

• Add support for bash's coproc and extended globbing like @(foo)
• Improve test coverage, adding tests to cmd/shfmt and bringing parser and printer close to 100%
• Support empty C-style for loops like for ((;;)) ...
• Support for the >| redirect operand
• cmd/shfmt
  • Fix issue where .sh and .bash files might not be walked if running on a directory
  • Fix issue where -p was not obeyed when formatting stdin
• parser
  • $'' now generates an ast.SglQuoted, not an ast.Quoted
  • Support for ambiguous (( like with $((
  • Improve special parameter expansions like $@ or $!
  • Improve bash's export typeset, nameref and readonly
  • <>, >& and <& are valid POSIX
  • Support for bash's ^, ^^, , and ,, operands inside ${}

• Optimizations all around, making shfmt ~15% faster
• cmd/shfmt
  • Add -p flag to only accept POSIX Shell programs (parser.PosixConformant)
• parser
  • Add support for ambiguous $(( as in $((foo) | bar)
  • Limit more bash features to PosixConformant being false
  • Don't parse heredoc bodies in nested expansions and contexts
  • Run tests through bash to confirm the presence of a parse error
• ast
  • Add Walk(Visitor, Node) function

Initial release.