[all-commits] [llvm/llvm-project] 185d49: [lldb] Introduce dwim-print command

[Dave Lee via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 185d4964a1584cedc3385adb4d6ed863c71f6515
      https://github.com/llvm/llvm-project/commit/185d4964a1584cedc3385adb4d6ed863c71f6515
  Author: Dave Lee <davelee.com at gmail.com>
  Date:   2022-11-29 (Tue, 29 Nov 2022)

  Changed paths:
    M lldb/include/lldb/Core/Debugger.h
    M lldb/include/lldb/lldb-enumerations.h
    M lldb/source/Commands/CMakeLists.txt
    A lldb/source/Commands/CommandObjectDWIMPrint.cpp
    A lldb/source/Commands/CommandObjectDWIMPrint.h
    M lldb/source/Core/CoreProperties.td
    M lldb/source/Core/Debugger.cpp
    M lldb/source/Interpreter/CommandInterpreter.cpp
    A lldb/test/API/commands/dwim-print/Makefile
    A lldb/test/API/commands/dwim-print/TestDWIMPrint.py
    A lldb/test/API/commands/dwim-print/main.c

  Log Message:
  -----------
  [lldb] Introduce dwim-print command

Implements `dwim-print`, a printing command that chooses the most direct,
efficient, and resilient means of printing a given expression.

DWIM is an acronym for Do What I Mean. From Wikipedia, DWIM is described as:

  > attempt to anticipate what users intend to do, correcting trivial errors
  > automatically rather than blindly executing users' explicit but
  > potentially incorrect input

The `dwim-print` command serves as a single print command for users who don't
yet know, or prefer not to know, the various lldb commands that can be used to
print, and when to use them.

This initial implementation is the base foundation for `dwim-print`. It accepts
no flags, only an expression. If the expression is the name of a variable in
the frame, then effectively `frame variable` is used to get, and print, its
value. Otherwise, printing falls back to using `expression` evaluation. In this
initial version, frame variable paths will be handled with `expression`.

Following this, there are a number of improvements that can be made. Some
improvements include supporting `frame variable` expressions or registers.

To provide transparency, especially as the `dwim-print` command evolves, a new
setting is also introduced: `dwim-print-verbosity`. This setting instructs
`dwim-print` to optionally print a message showing the effective command being
run. For example `dwim-print var.meth()` can print a message such as: "note:
ran `expression var.meth()`".

See https://discourse.llvm.org/t/dwim-print-command/66078 for the proposal and
discussion.

Differential Revision: https://reviews.llvm.org/D138315