Common Build Tools

This file defines general utilities that abstract common build functionality and provides some common concrete build functions.

General Utilities

def Lake.platformTrace : Lake.Hash

Build trace for the host platform. If an artifact includes this in its trace, it is platform-dependent and will be rebuilt on different host platforms.

Equations

• Lake.platformTrace = Lake.pureHash System.Platform.target

structure Lake.BuildMetadata : Type

The build trace file format, which stores information about a (successful) build.

• depHash : Lake.Hash
• log : Lake.Log

instance Lake.instToJsonBuildMetadata : Lean.ToJson Lake.BuildMetadata

Equations

• Lake.instToJsonBuildMetadata = { toJson := Lake.toJsonBuildMetadata✝ }

def Lake.BuildMetadata.ofHash (h : Lake.Hash) : Lake.BuildMetadata

Equations

• Lake.BuildMetadata.ofHash h = { depHash := h, log := ∅ }

def Lake.BuildMetadata.fromJson? (json : Lean.Json) : Except String Lake.BuildMetadata

Equations

• Lake.BuildMetadata.fromJson? json = do let obj ← Lake.JsonObject.fromJson? json let depHash ← obj.get "depHash" let log ← obj.getD "log" ∅ pure { depHash := depHash, log := log }

instance Lake.instFromJsonBuildMetadata : Lean.FromJson Lake.BuildMetadata

Equations

• Lake.instFromJsonBuildMetadata = { fromJson? := Lake.BuildMetadata.fromJson? }

def Lake.readTraceFile? (path : System.FilePath) : Lake.LogIO (Option Lake.BuildMetadata)

Read persistent trace data from a file.

Equations

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def Lake.writeTraceFile (path : System.FilePath) (depTrace : Lake.BuildTrace) (log : Lake.Log) : IO Unit

Write persistent trace data to a file.

Equations

• Lake.writeTraceFile path depTrace log = do Lake.createParentDirs path let data : Lake.BuildMetadata := { depHash := depTrace.hash, log := log } IO.FS.writeFile path (Lean.toJson data).pretty

@[specialize #[]]

def Lake.checkHashUpToDate {ι : Type u_1} [Lake.CheckExists ι] [Lake.GetMTime ι] (info : ι) (depTrace : Lake.BuildTrace) (depHash : Option Lake.Hash) (oldTrace : Lake.MTime := depTrace.mtime) : Lake.JobM Bool

Checks if the info is up-to-date by comparing depTrace with depHash. If old mode is enabled (e.g., --old), uses the oldTrace modification time as the point of comparison instead.

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@[specialize #[]]

def Lake.buildUnlessUpToDate? {ι : Type u_1} [Lake.CheckExists ι] [Lake.GetMTime ι] (info : ι) (depTrace : Lake.BuildTrace) (traceFile : System.FilePath) (build : Lake.JobM PUnit) (action : Lake.JobAction := Lake.JobAction.build) (oldTrace : Lake.MTime := depTrace.mtime) : Lake.JobM Bool

Checks whether info is up-to-date, and runs build to recreate it if not. If rebuilt, saves the new depTrace and build log to traceFile. Returns whether info was already up-to-date.

Up-to-date Checking

If traceFile exists, checks that the hash in depTrace matches that of the traceFile. If not, and old mode is enabled (e.g., --old), falls back to the oldTrace modification time as the point of comparison. If up-to-date, replay the build log stored in traceFile.

If traceFile does not exist, checks that info has a newer modification time then depTrace / oldTrace. No log will be replayed.

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def Lake.buildUnlessUpToDate?.go (depTrace : Lake.BuildTrace) (traceFile : System.FilePath) (build : Lake.JobM PUnit) (action : Lake.JobAction := Lake.JobAction.build) : Lake.JobM Bool

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@[inline]

def Lake.buildUnlessUpToDate {ι : Type u_1} [Lake.CheckExists ι] [Lake.GetMTime ι] (info : ι) (depTrace : Lake.BuildTrace) (traceFile : System.FilePath) (build : Lake.JobM PUnit) (action : Lake.JobAction := Lake.JobAction.build) (oldTrace : Lake.MTime := depTrace.mtime) : Lake.JobM PUnit

Checks whether info is up-to-date, and runs build to recreate it if not. If rebuilt, saves the new depTrace and build log to traceFile.

See buildUnlessUpToDate? for more details on how Lake determines whether info is up-to-date.

Equations

• Lake.buildUnlessUpToDate info depTrace traceFile build action oldTrace = discard (Lake.buildUnlessUpToDate? info depTrace traceFile build action oldTrace)

def Lake.cacheFileHash (file : System.FilePath) : IO Unit

Computes the hash of a file and saves it to a .hash file.

Equations

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def Lake.clearFileHash (file : System.FilePath) : IO Unit

Remove the cached hash of a file (its .hash file).

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def Lake.fetchFileHash (file : System.FilePath) (text : Bool := false) : Lake.JobM Lake.Hash

Fetches the hash of a file that may already be cached in a .hash file. If hash files are not trusted (e.g., with --rehash) or the .hash file does not exist, it will be created with a newly computed hash.

If text := true, file is hashed as a text file rather than a binary file.

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def Lake.fetchFileTrace (file : System.FilePath) (text : Bool := false) : Lake.JobM Lake.BuildTrace

Fetches the trace of a file that may have already have its hash cached in a .hash file. If no such .hash file exists, recomputes and creates it.

If text := true, file is hashed as text file rather than a binary file.

Equations

• Lake.fetchFileTrace file text = do let __do_lift ← Lake.fetchFileHash file text let __do_lift_1 ← liftM (Lake.getMTime file) pure { hash := __do_lift, mtime := __do_lift_1 }

def Lake.buildFileUnlessUpToDate (file : System.FilePath) (depTrace : Lake.BuildTrace) (build : Lake.JobM PUnit) (text : Bool := false) : Lake.JobM Lake.BuildTrace

Builds file using build unless it already exists and depTrace matches the trace stored in the .trace file. If built, save the new depTrace and cache file's hash in a .hash file. Otherwise, try to fetch the hash from the .hash file using fetchFileTrace. Build logs (if any) are saved to a .log.json file and replayed from there if the build is skipped.

For example, given file := "foo.c", compares depTrace with that in foo.c.trace with the hash cached in foo.c.hash and the log cached in foo.c.trace.

If text := true, file is hashed as a text file rather than a binary file.

Equations

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@[inline]

def Lake.buildFileAfterDep {α : Type u_1} (file : System.FilePath) (dep : Lake.BuildJob α) (build : α → Lake.JobM PUnit) (extraDepTrace : Lake.JobM Lake.BuildTrace := pure Lake.BuildTrace.nil) (text : Bool := false) : Lake.SpawnM (Lake.BuildJob System.FilePath)

Build file using build after dep completes if the dependency's trace (and/or extraDepTrace) has changed.

If text := true, file is handled as a text file rather than a binary file.

Equations

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@[inline]

def Lake.buildFileAfterDepList {α : Type u_1} (file : System.FilePath) (deps : List (Lake.BuildJob α)) (build : List α → Lake.JobM PUnit) (extraDepTrace : Lake.JobM Lake.BuildTrace := pure Lake.BuildTrace.nil) (text : Bool := false) : Lake.SpawnM (Lake.BuildJob System.FilePath)

Build file using build after deps have built if any of their traces change.

If text := true, file is handled as a text file rather than a binary file.

Equations

• Lake.buildFileAfterDepList file deps build extraDepTrace text = Lake.buildFileAfterDep file (Lake.BuildJob.collectList deps) build extraDepTrace text

@[inline]

def Lake.buildFileAfterDepArray {α : Type u_1} (file : System.FilePath) (deps : Array (Lake.BuildJob α)) (build : Array α → Lake.JobM PUnit) (extraDepTrace : Lake.JobM Lake.BuildTrace := pure Lake.BuildTrace.nil) (text : Bool := false) : Lake.SpawnM (Lake.BuildJob System.FilePath)

Build file using build after deps have built if any of their traces change.

If text := true, file is handled as a text file rather than a binary file.

Equations

• Lake.buildFileAfterDepArray file deps build extraDepTrace text = Lake.buildFileAfterDep file (Lake.BuildJob.collectArray deps) build extraDepTrace text

Common Builds

def Lake.inputBinFile (path : System.FilePath) : Lake.SpawnM (Lake.BuildJob System.FilePath)

A build job for binary file that is expected to already exist (e.g., a data blob).

Any byte difference in a binary file will trigger a rebuild of its dependents.

Equations

• Lake.inputBinFile path = Lake.Job.async ((fun (x : Lake.BuildTrace) => (path, x)) <$> Lake.computeTrace path)

def Lake.inputTextFile (path : System.FilePath) : Lake.SpawnM (Lake.BuildJob System.FilePath)

A build job for text file that is expected to already exist (e.g., a source file).

Text file traces have normalized line endings to avoid unnecessary rebuilds across platforms.

Equations

• Lake.inputTextFile path = Lake.Job.async ((fun (x : Lake.BuildTrace) => (path, x)) <$> Lake.computeTrace { path := path })

@[inline]

def Lake.inputFile (path : System.FilePath) (text : Bool) : Lake.SpawnM (Lake.BuildJob System.FilePath)

A build job for file that is expected to already exist (e.g., a data blob or source file).

If text := true, the file is handled as a text file rather than a binary file. Any byte difference in a binary file will trigger a rebuild of its dependents. In contrast, text file traces have normalized line endings to avoid unnecessary rebuilds across platforms.

Equations

• Lake.inputFile path text = if text = true then Lake.inputTextFile path else Lake.inputBinFile path

@[inline]

def Lake.buildO (oFile : System.FilePath) (srcJob : Lake.BuildJob System.FilePath) (weakArgs traceArgs : Array String := #[]) (compiler : System.FilePath := { toString := "cc" }) (extraDepTrace : Lake.JobM Lake.BuildTrace := pure Lake.BuildTrace.nil) : Lake.SpawnM (Lake.BuildJob System.FilePath)

Build an object file from a source file job using compiler. The invocation is:

compiler -c -o oFile srcFile weakArgs... traceArgs...

The traceArgs are included as part of the dependency trace hash, whereas the weakArgs are not. Thus, system-dependent options like -I or -L should be weakArgs to avoid build artifact incompatibility between systems (i.e., a change in the file path should not cause a rebuild).

You can add more components to the trace via extraDepTrace, which will be computed in the resulting BuildJob before building.

Equations

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@[inline]

def Lake.buildLeanO (oFile : System.FilePath) (srcJob : Lake.BuildJob System.FilePath) (weakArgs traceArgs : Array String := #[]) : Lake.SpawnM (Lake.BuildJob System.FilePath)

Build an object file from a source fie job (i.e, a lean -c output) using leanc.

Equations

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def Lake.buildStaticLib (libFile : System.FilePath) (oFileJobs : Array (Lake.BuildJob System.FilePath)) : Lake.SpawnM (Lake.BuildJob System.FilePath)

Build a static library from object file jobs using the ar packaged with Lean.

Equations

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def Lake.buildLeanSharedLib (libFile : System.FilePath) (linkJobs : Array (Lake.BuildJob System.FilePath)) (weakArgs traceArgs : Array String := #[]) : Lake.SpawnM (Lake.BuildJob System.FilePath)

Build a shared library by linking the results of linkJobs using leanc.

Equations

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def Lake.buildLeanExe (exeFile : System.FilePath) (linkJobs : Array (Lake.BuildJob System.FilePath)) (weakArgs traceArgs : Array String := #[]) : Lake.SpawnM (Lake.BuildJob System.FilePath)

Build an executable by linking the results of linkJobs using leanc.

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def Lake.buildLeanSharedLibOfStatic (staticLibJob : Lake.BuildJob System.FilePath) (weakArgs traceArgs : Array String := #[]) : Lake.SpawnM (Lake.BuildJob System.FilePath)

Build a shared library from a static library using leanc.

Equations

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def Lake.computeDynlibOfShared (sharedLibTarget : Lake.BuildJob System.FilePath) : Lake.SpawnM (Lake.BuildJob Lake.Dynlib)

Construct a Dynlib object for a shared library target.

Equations

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