When printing an ObjC object, which is a pointer, lldb has handled it
the same way it treats any other pointer – printing only class name and
pointer address. The object is not expanded, its children are not shown.
This change updates `dwim-print` to print objc pointers by expanding (ie
dereferencing), with the assumption that it's what the user wants.
Note that this is currently possible using the `--ptr-depth`/`-P` flag.
With this change, when `dwim-print` prints root level objc objects, it's
the same effect as using `--ptr-depth 1`.
An (unmeasured) improvement to performance of `dwim-print` when used as `po`.
This change lifts the check for `note_shown` to the top of the lambda, to avoid all subsequent work when the hint has already been shown. The main effect is to avoid performing a regex match when the hint is not going to be shown.
This change also constructs the `std::regex` only once, by making it static.
There are a lot of lldb commands whose result is really one or more
ValueObjects that we then print with the ValueObjectPrinter. Now that we
have the ability to access the SBCommandReturnObject through a callback
(#125006), we can store the resultant ValueObjects in the return object,
allowing an IDE to access the SBValues and do its own rich formatting.
rdar://143965453
`frame variable` supports nested variable access, which the API calls "variable
expression paths". This change updates `dwim-print` to support a subset of supported
variable expression paths.
Consider the expression `a->b`. In C++, the arrow operator can be overloaded, and where
that is the case, expression evaluation must be used to evaluate it, not frame variable.
Likewise, the subscript operator can be overloaded.
To avoid those cases, this change introduces a limited support for variable expression
paths. Use of the dot operator is allowed.
Additionally, this change allows `dwim-print` to directly access children of `this` and
`self` (see AllowDirectIVarAccess). This functionality is also provided by the same
`GetValueForVariableExpressionPath` method.
rdar://104348908
ValueObject is part of lldbCore for historical reasons, but conceptually
it deserves to be its own library. This does introduce a (link-time) circular
dependency between lldbCore and lldbValueObject, which is unfortunate
but probably unavoidable because so many things in LLDB rely on
ValueObject. We already have cycles and these libraries are never built
as dylibs so while this doesn't improve the situation, it also doesn't
make things worse.
The header includes were updated with the following command:
```
find . -type f -exec sed -i.bak "s%include \"lldb/Core/ValueObject%include \"lldb/ValueObject/ValueObject%" '{}' \;
```
This allows IDEs to render LLDB expression diagnostics to their liking
without relying on characterprecise ASCII art from LLDB. It is exposed
as a versioned SBStructuredData object, since it is expected that this
may need to be tweaked based on actual usage.
Previously the result would get overwritten by a success on all code
paths.
This is another NFC change for TypeSystemClang, because an object
description cannot actually fail there. It will have different behavior
in the Swift plugin.
This change by itself has no measurable effect on the LLDB
testsuite. I'm making it in preparation for threading through more
errors in the Swift language plugin.
that separates out language and version. To avoid reinventing the wheel
and introducing subtle incompatibilities, this API uses the table of
languages and versiond defined by the upcoming DWARF 6 standard
(https://dwarfstd.org/languages-v6.html). While the DWARF 6 spec is not
finialized, the list of languages is broadly considered stable.
The primary motivation for this is to allow the Swift language plugin to
switch between language dialects between, e.g., Swift 5.9 and 6.0 with
out introducing a ton of new language codes. On the main branch this
change is considered NFC.
Depends on https://github.com/llvm/llvm-project/pull/89980
The code that prints ValueObjects is duplicated across two different
cases of the dwim-print command, and a subsequent commit will add a
third case. As such, this commit factors out the common code into a
lambda. A free function was considered, but there is too much
function-local context required in that.
We also reword some of the comments so that they stop counting cases,
making it easier to add other cases later.
`EvaluateExpression` does not always create a new persistent result. If the expression
is a bare persistent variable, then a new persistent result is not created. This means
the caller can't assume a new persistent result is created for each evaluation.
However, `dwim-print` was doing exactly that: assuming a new persistent result for each
evaluation. This resulted in a bug:
```
(lldb) p int $j = 23
(lldb) p $j
(lldb) p $j
```
The first `p $j` would not create a persistent result, and so `dwim-print` would
inadvertently delete `$j`. The second `p $j` would fail.
The fix is to try `expr` as a persistent variable, after trying `expr` as a frame
variable. For persistent variables, this avoids calling `EvaluateExpression`.
Resolves https://github.com/llvm/llvm-project/issues/84806
rdar://124688427
Partly, there's just a lot of unnecessary boiler plate. It's also
possible to define combinations of arguments that make no sense (e.g.
eArgRepeatPlus followed by eArgRepeatPlain...) but these are never
checked since we just push_back directly into the argument definitions.
This commit is step 1 of this cleanup - do the obvious stuff. In it, all
the simple homogenous argument lists and the breakpoint/watchpoint
ID/Range types, are set with common functions. This is an NFC change, it
just centralizes boiler plate. There's no checking yet because you can't
get a single argument wrong.
The end goal is that all argument definition goes through functions and
m_arguments is hidden so that you can't define inconsistent argument
sets.
This is a follow-on to:
https://github.com/llvm/llvm-project/pull/82085
The completer for register names was missing from the argument table. I
somehow missed that the only register completer test was x86_64, so that
test broke.
I added the completer in to the right slot in the argument table, and
added a small completions test that just uses the alias register names.
If we end up having a platform that doesn't define register names, we'll
have to skip this test there, but it should add a sniff test for
register completion that will run most everywhere.
This reverts commit 21631494b068d9364b8dc8f18e59adee9131a0a5.
Reverted because of greendragon failure:
******************** TEST 'lldb-api :: functionalities/completion/TestCompletion.py' FAILED ********************
Script:
Most commands were adding argument completion handling by themselves,
resulting in a lot of unnecessary boilerplate. In many cases, this could
be done generically given the argument definition and the entries in the
g_argument_table.
I'm going to address this in a couple passes. In this first pass, I
added handling of commands that have only one argument list, with one
argument type, either single or repeated, and changed all the commands
that are of this sort (and don't have other bits of business in their
completers.)
I also added some missing connections between arg types and completions
to the table, and added a RemoteFilename and RemotePath to use in places
where we were using the Remote completers. Those arguments used to say
they were "files" but they were in fact remote files.
I also added a module arg type to use where we were using the module
completer. In that case, we should call the argument module.
[lldb] Part 2 of 2 - Refactor `CommandObject::DoExecute(...)` to return
`void` instead of ~~`bool`~~
Justifications:
- The code doesn't ultimately apply the `true`/`false` return values.
- The methods already pass around a `CommandReturnObject`, typically
with a `result` parameter.
- Each command return object already contains:
- A more precise status
- The error code(s) that apply to that status
Part 1 refactors the `CommandObject::Execute(...)` method.
- See
[https://github.com/llvm/llvm-project/pull/69989](https://github.com/llvm/llvm-project/pull/69989)
rdar://117378957
The `po` alias now matches the behavior of the `expression` command when
the it can apply a Fix-It to an expression.
Modifications
- Add has `m_fixed_expression` to the `CommandObjectDWIMPrint` class a
`protected` member that stores the post Fix-It expression, just like the
`CommandObjectExpression` class.
- Converted messages to present tense.
- Add test cases that confirms a Fix-It for a C++ expression for both
`po` and `expressions`
rdar://115317419
The `po` alias now matches the behavior of the `expression` command when
the it can apply a Fix-It to an expression.
Modifications
- Add has `m_fixed_expression` to the `CommandObjectDWIMPrint` class a
`protected` member that stores the post Fix-It expression, just like the
`CommandObjectExpression` class.
- Converted messages to present tense.
- Add test cases that confirms a Fix-It for a C++ expression for both
`po` and `expressions`
rdar://115317419
Co-authored-by: Pete Lawrence <plawrence@apple.com>
Lots of users use "po" as their default print command. If the type
doesn't implement the description function the output is often not what
the user wants. Print a hint telling the user that they might prefer
using "p" instead.
Differential Revision: https://reviews.llvm.org/D153489
This patch should allow the user to set specific auto-completion type
for their custom commands.
To do so, we had to hoist the `CompletionType` enum so the user can
access it and add a new completion type flag to the CommandScriptAdd
Command Object.
So now, the user can specify which completion type will be used with
their custom command, when they register it.
This also makes the `crashlog` custom commands use disk-file completion
type, to browse through the user file system and load the report.
Differential Revision: https://reviews.llvm.org/D152011
Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
Expression evaluation for `void` valued expressions sets an error using the `kNoResult`
code. Like the `expression` command, `dwim-print` should also not print such errors.
Before:
```
(lldb) dwim-print (void)printf("hi\n")
hi
Error: 'unknown error'
```
After:
```
(lldb) dwim-print (void)printf("hi\n")
hi
```
rdar://109746544
Differential Revision: https://reviews.llvm.org/D151351
Follow up to "Suppress persistent result when running po" (D144044).
This change delays removal of the persistent result until after `Dump` has been called.
In doing so, the persistent result is available for the purpose of getting its object
description.
In the original change, the persistent result removal happens indirectly, by setting
`EvaluateExpressionOptions::SetSuppressPersistentResult`. In practice this has worked,
however this exposed a latent bug in swift-lldb. The subtlety, and the bug, depend on
when the persisteted result variable is removed.
When the result is removed via `SetSuppressPersistentResult`, it happens within the call
to `Target::EvaluateExpression`. That is, by the time the call returns, the persistent
result is already removed.
The issue occurs shortly thereafter, when `ValueObject::Dump` is called, it cannot make
use of the persistent result variable (instead it uses the `ValueObjectConstResult`). In
swift-lldb, this causes an additional expression evaluation to happen. It first tries an
expression that reference `$R0` etc, but that always fails because `$R0` is removed. The
fallback to this failure does work most of the time, but there's at least one bug
involving imported Clang types.
Differential Revision: https://reviews.llvm.org/D150619
When printing a value, allow the root value's name to be elided, without omiting the
names of child values.
At the API level, this adds `SetHideRootName()`, which joins the existing
`SetHideName()` function.
This functionality is used by `dwim-print` and `expression`.
Fixes an issue identified by @jgorbe in https://reviews.llvm.org/D145609.
Differential Revision: https://reviews.llvm.org/D146783
Change `dwim-print` to now disable persistent results by default, unless requested by
the user with the `--persistent-result` flag.
Ex:
```
(lldb) dwim-print 1 + 1
(int) 2
(lldb) dwim-print --persistent-result on -- 1 + 1
(int) $0 = 2
```
Users who wish to enable persistent results can make and use an alias that includes
`--persistent-result on`.
Updates: To recommit this, both TestPersistentResult.py and TestPAlias.py needed to be
updated, as well as the changes in D146230.
Differential Revision: https://reviews.llvm.org/D145609
Change `dwim-print` to now disable persistent results by default, unless requested by
the user with the `--persistent-result` flag.
Ex:
```
(lldb) dwim-print 1 + 1
(int) 2
(lldb) dwim-print --persistent-result on -- 1 + 1
(int) $0 = 2
```
Users who wish to enable persistent results can make and use an alias that includes
`--persistent-result on`.
Differential Revision: https://reviews.llvm.org/D145609
Context: The `expression` command uses artificial variables to store the expression
result. This result variable is unconditionally kept around after the expression command
has completed. These variables are known as persistent results. These are the variables
`$0`, `$1`, etc, that are displayed when running `p` or `expression`.
This change allows users to control whether result variables are persisted, by
introducing a `--persistent-result` flag.
This change keeps the current default behavior, persistent results are created by
default. This change gives users the ability to opt-out by re-aliasing `p`. For example:
```
command unalias p
command alias p expression --persistent-result false --
```
For consistency, this flag is also adopted by `dwim-print`. Of note, if asked,
`dwim-print` will create a persistent result even for frame variables.
Differential Revision: https://reviews.llvm.org/D144230
Adopt `expression`'s options in `dwim-print`.
This is primarily added to support the `--language`/`-l` flag.
Differential Revision: https://reviews.llvm.org/D144114
Add support for the `--gdb-format`/`-G` flag to `dwim-print`.
The gdb-format flag allows users to alias `p` to `dwim-print`.
Differential Revision: https://reviews.llvm.org/D141425
Allow `dwim-print` to evaluate expressions using the dummy target if no real
target exists.
This adds some parity to `expression`. With this, both of the following work:
```
lldb -o 'expr 1+2'
lldb -o 'dwim-print 1+2'
```
Differential Revision: https://reviews.llvm.org/D138960
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
