Release notes

2021.1

Refactorings

• New: Inline Variable refactoring for local let bindings
• Rename: when renaming a type that has an associated module with the same name, the module is also suggested to be renamed (and vice versa)
• Introduce Variable: redundant parens are removed for some replaced expressions

Language version support

• New: Allowed language level is calculated based on a project and the compiler used in the build
  • Allows implementing analyzers and other features that use or suggest newer language features

Analyzers:

• To Interpolated string suggestion + quick fix for F# 5.0+, by @saul (#221)
• Replace __ with _ analyzer + quick fix for F# 4.7+
• Redundant parens analyzer + quick fix for parens in patterns, types, and simple expressions
• Various improvements to other analyzers and quick fixes

Quick fixes

• Specify parameter type when it's inferred below
• Use ; list separator
• Replace type abbreviation with abbreviated type in type augmentation

Type providers

• Host type providers out-of-process
  • Uses the same runtime as the build, fixes various issues previously occurred with the Rider runtime

• Run icon for main methods
• Use .NET Core references for scripts by default
• Fixes in File Structure for interface/extension members
• Various fixes in C# interop
• Typing assists for braces in string interpolations

2020.1

Inspections / analyzers

• Attributes

  • Add Redundant Attribute suffix analyzer and quick fix (by @reacheight (#109))
  • Add Redundant attribute parens analyzer and quick fix (by @reacheight (#104))

• Run analyzers in parallel

• Optimize spell-checker analyzer

• Fix Spell-checker didn't work on some declarations

• Improve reported ranges for unused sequential and let expressions

Quick fixes

• FS0039: Undefined name

  • Better types filtering in Import Type quick fix
  • Escape module names when importing types
  • Fix various cases of incorrect open placement

• FS0003: Not a function / unexpected argument

  • Add Remore unexpected arguments (by @DedSec256 (#89))

• FS0026: match rule is never matched

  • Remove never matching rules (by @reacheight (#74))

• FS0005: Field not mutable

  • Add Make field mutable

• FS0027: Value not mutable

  • Add Make value mutable

• FS1182: Unused let binding

  • Add Rename with _ prefix

• FS0038: Var bound twice

  • Add Replace with _

• Add parens to expression when applying quick fixes where needed

Intentions / Context actions

• Add Elif to If, If to Elif actions
• Add Negate If expression condition

Code vision

• Add Copy Inferred Type action
• Add Don't show parent namespaces for types
• Fix Nested tuple params could be shown wrong

C# interop

• Fix Symbols from C# projects could not be seen after first build
• Fix Support for single case unions that are parsed as type abbreviations
• Fix Invalid accessibility for some types containing non-public members
• Fix Attributes containing Attribute wasn't seen properly from C# (e.g. AttributeUsage)

F# Interactive

• Add Send project references to F# Interactive action
• Fix Send to F# Interactive is now available during initial file indexing

Debugger

• Add More expressions are supported in evaluation on mouse hover:
  • self-reference qualifiers in methods and types (this.Property)
  • indexer expressions ("foo".[1])

Find usages and Rename

• Fix Types would not be found inside generic constraints, constructor attributes, and measures
• Fix New Instance Creation wasn't reported for new expressions
• Better naming style suggestions for literals

Highlighting

Add Highlight more escape sequences in strings Add Settings for F# preprocessor keywords Fix Highlighting for const keyword

• Add Type file template
• Select whole () expression in Extend Selection
• Fix Plugin could not be built on case-sensitive file systems (by @ mcon (#108))

2019.3

Tools update and internals

• Update FSharp.Compiler.Service with F# 4.7 support, most notably:
  • _ self identifier in member definitions
  • Implicit yield in computational expressions
  • F# 5.0 features preview when enabled with compiler option
• Update Fantomas to 3.0 with various fixes
• Rewritten parse tree nodes for expressions and types
  • Allows significantly simplified code for features like quick fixes, analyzers, and others
  • Better context tracking, optimized references creation, references are now qualifier-aware
  • Improved infrastructure for upcoming refactorings, postfix templates, and other features

Quick fixes

• FS0039: Undefined name
  • Add Initial Import Type quick fix
  • Add Make outer function recursive fix
• FS0020: Expression is unused
  • Add Introduce 'let' binding fix for local expressions
  • Update Ignore expression fix
    • Better |> ignore placement for multiline expressions
    • Option to ignore inner expression in match and if expressions
  • Add Remove subsequent expressions fix
• FS1182: Unused let binding
  • Add Remove unused local binding
• FS0597: Successive arguments should be separated by spaces, tupled, or parenthesized
  • Add Surround with parens fix
• FS0001: Unit type expected
  • Add Ignore expression fix for if expressions without else branch
• FS0066: Unnecessary upcast
  • Add Remove upcast fix
• FS0588: Expected expression after let
  • Add Replace let with bound expression fix
• FS0576: and is not allowed for non-recursive let bindings
  • Add To recursive let bindings fix
• FS0894: Let bindings inside class cannot be inline
  • Add Remove inline fix

Inspections / Problem analyzers

• Redundant new analyzer
  • Add Remove redundant new fix
• Redundant identifier escaping
  • Add Remove backticks fix
• Add Extension attribute usage analyzer:
  • Extension member inside non-extension type
  • Extension type doesn't define extension members
  • Extension type should be static

Rename

• Rename additional symbols:
  • Suggest renaming of a single case union when renaming its case and vice versa
• Suggest camelCase names for let bindings
• Add renaming anonymous records fields
• Fix renaming union case fields when used as named args
• Fix renaming typed parameters inside lambda functions
• Better naming sugestions for predefined types

Intentions / Context actions

• Add To namespace/module action
• Add To recursive module or namespace action

Extend selection

• Rewritten from scratch for the parse tree changes
  • Words are selected first when invoked inside comments and strings
  • Better selection for many language constructs, with contributions by @reacheight
  • Fix declaration selection could miss starting keywords and attributes

Find usages

• Parts of results grouping is rewritten from scratch for the parse tree changes
  • Fix various cases could be reported incorrectly

Typing assistance

• Significantly improved undo/redo changes workflow
• Add Complete pair escape identifier backticks assist
• Add Escape identifier with backticks assist
• Add Erase trailing semicolon in Enter assist when enabled in Code Style settings
• Fix Pair quotes assists no longer applied inside comments
• Update Better indentation in Enter assist

Highlighting

• Separate highlighting options for F#:
  • Add F#-specific symbols like Unions or Active Patterns can now be highligted differently
• Add Highlight byref values as mutable
• Fix unary operators highlighting

• Add option to specify language version for scripts and F# Interactive
• Fix Don't use auto-detected code style settings in Reformat Code action
• Add helper for Quick Definition
• Fix record private representations resolve in C#
• Fix adding new file to a project could fail
• Update adding open now adds empty line when needed, by @saul (#65)
• Update Ignore Folders on top option in F# projects
• Fix getting F# Interactive paths
• Fix resolve of extension members with specified compiled names
• Update Don't show inferred type lenses inside object expressions

2019.2

Code Vision support

• Inferred types are shown for functions, values and members
• Version control author is shown for declarations

Code analysis

• R# spell checker now works for F# symbol declarations, strings and comments
• Escape sequences are highlighted in strings
• Better highlighting of never matched rules in match expressions

Refactorings

• Context-based rename suggestions

Quick Fixes

• Generate missing record fields
• Ignore unused expression
• Remove unused self identifier in types
• Remove unused as pattern
• Replace unused pattern with _
• Replace use with let in modules and types
• Add missing rec in let ... and bindings

Find Usages & navigation

• Find Usages and Go to Declaration now work for record construction and copy-and-update expressions
• New Instance occurrence kind is shown for F# exception creation expressions

• Allow running F# Interactive from .NET Core SDK 2.2.300+

Fixes

• Completion for names starting with _ is fixed
• Fix resolve for same type defined in different projects or assemblies
• Fix resolve for members with same signature in a type and interface implementation in it
• Rename wouldn't work for some local values
• Lexing of attributes inside type application was fixed by @misonijnik (#51)

2019.1

Refactorings

• Rename
  • Cross-language rename for F#-defined symbols
  • Name suggestions based on symbol type

Navigation and cross-language interop

• Go to next/previous/containing member actions now work for top level let bindings
• Global navigation and Go to File Member action now work for type-private let bindings
• F# defined delegates are now supported and are properly seen by code in other languages
• Intrinsic type extensions are now considered type parts with navigation working for every part
• Navigation to compiler generated members declarations from usages in other languages now navigates to origin members
• Navigation to symbols with escaped names now places caret inside escaped identifiers
• outref and inref types are now properly seen in other languages

Find usages

• Usages inside let bindings are properly grouped by containing members
• Separate grouping for new occurrence kinds:
  • Type argument
  • Base type
  • Type checking
  • Type conversions
  • Module or namespace import
  • Write
  • Attribute reference
• Highlight Usages in File action now highlights Write occurrences differently to other occurrences
• Find usages of union cases now also searches for compiler generated union members

Code editing and completion

• An option for out-of-scope completion to place open statements to the top level was added and enabled by default by @saul (#39)
• Out-of-scope completion can be disabled now
• New Surround with Parens typing assist

Code analysis

• FSharp.Compiler.Service updated with anonymous records support
• Format specifiers are now highlighted, by @vasily-kirichenko (#40)
• Inferred generic arguments are shown in tooltips, by @vasily-kirichenko (#44)
• Full member names are shown in tooltips, by @vasily-kirichenko (#45)
• Debugger now shows local symbols values next to their uses
• Unused local values analysis is now turned on for all projects and scripts by default
• Support TreatWarningsAsErrors MSBuild property

• Notification about F# projects having wrong project type guid in solution file
• F# Interactive in FSharp.Compiler.Tools is now automatically found in non-SDK projects
• FSharp.Compiler.Interactive.Settings.dll is now bundled to the plugin (so fsi object is available in scripts)
• F# breadcrumbs provider was added
• Add hotkey hint to Send to F# interactive action
• Provide F# project Azure scope for Azure plugin (#46)

Fixes

• Pair paren was not inserted in attributes list
• Tab left action (Shift+Tab) didn't work
• Tests defined as let bindings in types were not found
• Incremental lexers were not reused, by @misonijnik
• Type hierarchy action icon was shown in wrong places
• Usages of operators using their compiled names were highlighted incorrectly
• Find usages didn't work for compiled active patterns and some union cases
• Local rename didn't work properly for symbols defined in Or patterns
• Better highlighting of active pattern declarations
• Extend Selection works better for patterns and match expressions
• Resolve and navigation didn't work for optional extension members having the same name in a single module
• Secondary constructors resolve was broken in other languages
• Some reported errors were duplicated