[Lldb-commits] [PATCH] D70851: [lldb] s/FileSpec::Equal/FileSpec::Match

[Pavel Labath via Phabricator via lldb-commits]

labath created this revision.
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The FileSpec class is often used as a sort of a pattern -- one specifies
a bare file name to search, and we check if in matches the full file
name of an existing module (for example).

These comparisons used FileSpec::Equal, which had some support for it
(via the full=false argument), but it was not a good fit for this job.

For one, it did a symmetric comparison, which makes sense for a function
called "equal", but not for typical searches (when searching for
"/foo/bar.so", we don't want to find a module whose name is just
"bar.so"). This resulted in patterns like:

  if (FileSpec::Equal(pattern, file, pattern.GetDirectory()))

which would request a "full" match only if the pattern really contained
a directory. This worked, but the intended behavior was very unobvious.

On top of that, a lot of the code wanted to handle the case of an
"empty" pattern, and treat it as matching everything. This resulted in
conditions like:

  if (pattern && !FileSpec::Equal(pattern, file, pattern.GetDirectory())

which are nearly impossible to decipher.

This patch introduces a FileSpec::Match function, which does exactly
what most of FileSpec::Equal callers want, an asymmetric match between a
"pattern" FileSpec and a an actual FileSpec. Empty paterns match
everything, filename-only patterns match only the filename component.

I've tried to update all callers of FileSpec::Equal to use a simpler
interface. Those that hardcoded full=true have been changed to use
operator==. Those passing full=pattern.GetDirectory() have been changed
to use FileSpec::Match.

There was also a handful of places which hardcoded full=false. I've
changed these to use FileSpec::Match too. This is a slight change in
semantics, but it does not look like that was ever intended, and it was
more likely a result of a misunderstanding of the "proper" way to use
FileSpec::Equal.

[In an ideal world a "FileSpec" and a "FileSpec pattern" would be two
different types, but given how widespread FileSpec is, it is unlikely
we'll get there in one go. This at least provides a good starting point
by centralizing all matching behavior.]


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D70851

Files:
  lldb/include/lldb/Core/ModuleSpec.h
  lldb/include/lldb/Core/SourceManager.h
  lldb/include/lldb/Utility/FileSpec.h
  lldb/source/Breakpoint/Breakpoint.cpp
  lldb/source/Commands/CommandObjectSource.cpp
  lldb/source/Core/IOHandler.cpp
  lldb/source/Core/Module.cpp
  lldb/source/Core/SearchFilter.cpp
  lldb/source/Core/SourceManager.cpp
  lldb/source/Plugins/Platform/POSIX/PlatformPOSIX.cpp
  lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
  lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.cpp
  lldb/source/Symbol/CompileUnit.cpp
  lldb/source/Symbol/Declaration.cpp
  lldb/source/Symbol/SymbolContext.cpp
  lldb/source/Target/TargetList.cpp
  lldb/source/Target/ThreadPlanStepInRange.cpp
  lldb/source/Utility/FileSpec.cpp
  lldb/unittests/Utility/FileSpecTest.cpp

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