fix(build): TTY progress on Windows — hand the real stdout to buildkit - #14090
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The bake progress display goes through containerd/console, which on Windows only accepts the exact os.Stdin/Stdout/Stderr values (pointer identity in newMaster) and rejects everything else with "creating a console from a file is not supported on windows". The _console wrapper introduced to satisfy buildkit's console.File type-assert therefore could never pass that check: TTY progress silently fell back to plain in auto mode, and --progress=tty / --ansi always failed hard with "failed to get console". When the CLI stream was constructed from a real file — the interactive case, where it wraps os.Stdout — hand that genuine *os.File to NewDisplay so the identity check passes. File-less streams keep the wrapper, which works on Unix where only the descriptor matters. Fixes #14086 Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> Signed-off-by: Nicolas De Loof <nicolas.deloof@gmail.com>
glours
approved these changes
Aug 19, 2026
glours
enabled auto-merge (rebase)
August 19, 2026 08:14
ndeloof
disabled auto-merge
August 19, 2026 15:42
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Fixes #14086: TTY/colorized build progress was structurally broken on Windows.
The bake display goes through containerd/console, whose Windows
newMasteronly accepts the exactos.Stdin/Stdout/Stderrvalues — a pointer-identity check, not a capability probe. The_consolewrapper added to satisfy buildkit'sconsole.Filetype-assert could therefore never pass it:--progress=autosilently fell back to plain, and--progress=tty/--ansi alwaysfailed withfailed to get console: creating a console from a file is not supported on windows.The fix hands the genuine
*os.File(viastreams.Out.File()) toprogressui.NewDisplaywhen the CLI stream wraps a real file, which is the interactive case. File-less streams keep the wrapper, unchanged: TTY rendering still works on Unix there, where only the descriptor matters.🤖 Generated with Claude Code