Fix FSI pretty printing for anonymous records#19919
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Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Anonymous records were rendered with { } braces, identical to nominal records, because FSharpType.IsRecord returns true for both. Detect the anonymous case via the CLR name prefix `<>f__AnonymousType` and thread an isAnonRecord flag through ValueInfo.RecordValue / recordValueL / makeRecordL so they emit the already-defined leftBraceBar / rightBraceBar punctuation literals ({| / |}).
For anonymous records use a semicolon-separated horizontal layout (semiListL) instead of the vertical aboveListL used by nominal records - this matches how anon records are written in source.
Struct anonymous records (compiled to value-type variants of <>f__AnonymousType) are detected at the same place via reprty.IsValueType, carried on ValueInfo.RecordValue as isStruct, and rendered with the existing struct keyword layout inside recordValueL (mirroring how tupleValueL handles TupleType.Value).
The leftBraceBar / rightBraceBar literal definitions were moved out of the #if COMPILER block in TaggedText so they are also available in the FSharp.Core build of sformat.fs.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
…6116) Address CODE-QUALITY verifier feedback: 1. Replace `RecordValue of isAnonRecord: bool * isStruct: bool * ...` with a 3-case `RecordKind = Nominal | AnonReference | AnonStruct` so the impossible (isAnonRecord=false, isStruct=true) state is unrepresentable. Construction and consumption now use exhaustive matches. 2. Revert `semiListL` back to `aboveListL` for anon records. The list-combinator change was outside the original bug scope; the layout engine already chooses single-line rendering when content fits, so the only meaningful diff for anon records remains the brace tokens. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
After reverting recordValueL to aboveListL, multi-field anon records print across multiple lines. Split single-line substring assertions into opener/closer pairs (mirroring the nominal-record test) so the multi-line layout is accepted. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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…ting (#6116) Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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) Regenerate FSI printing baselines under tests/fsharp/core/printing/ so they reflect the new (correct) anon-record value printing introduced by PR #19919 (fix for issue #6116). Five baselines now show `= {| AnonRecordField2 = 11 |}` instead of `= { AnonRecordField2 = 11 }`; nominal-record value lines are unchanged. Also update tests/fsharp/core/anon/{lib.fs,test.fsx} assertions whose runtime sprintf `%A` expectations encoded the old anon-record rendering, including the struct anon record case whose ToString() now prefixes `struct {| ... |}`. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Resolve the tests/AheadOfTime/Trimming/check.ps1 size-baseline conflict by re-running the trimming publish and recording the measured sizes. Also shrink the FSharp.Core codegen added by #6116: make ReflectUtils.RecordKind a plain enum instead of a union (it is only pattern-matched, never compared), which removes the generated equality/comparison/Tag/ToString members. Measured net9.0 trimmed sizes (CI-calibrated against the unchanged FSharpMetadataResource test = 7609344): FSharp.Core.dll: 314880 -> 312832 (feature cost +1024 over base) StaticLinkedFSharpCore .dll: 9172992 -> 9170944 Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Local macOS publish over-reports FSharp.Core.dll trimmed size by ~1536 bytes vs the CI Windows build (the embedded F# signature resource differs by platform), so the FSharpMetadataResource test is not a valid calibration anchor. Adopt the exact sizes reported by the failing CI run. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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This was referenced Jun 23, 2026
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Fixes #6116
FSI printed anonymous records with
{ ... }(nominal record syntax) insteadof
{| ... |}. Now the printer detects anonymous record types and uses thecorrect delimiters, plus
struct {| ... |}for struct anonymous records.