This PR adds two features to the message testing commands:
## `#guard_panic` command
A new `#guard_panic` command that succeeds if the nested command
produces a panic message. Unlike `#guard_msgs`, it does not check the
exact message content, only that a panic occurred.
This is useful for testing commands that are expected to panic, where
the exact panic message text may be volatile. It is particularly useful
when minimizing a panic discovered "in the wild", while ensuring the
panic behaviour is preserved.
## `substring := true` option for `#guard_msgs`
Adds a `substring := true` option to `#guard_msgs` that checks if the
docstring appears as a substring of the output (after whitespace
normalization), rather than requiring an exact match. This is useful
when you only care about part of the message.
Example:
```lean
/-- Unknown identifier -/
#guard_msgs (substring := true) in
example : α := x
```
## Refactoring
Also refactors `runAndCollectMessages` as a shared helper function used
by both `#guard_msgs` and `#guard_panic`.
🤖 Prepared with Claude Code
---------
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
This PR adds `gcd_left_comm` lemmas for both `Nat` and `Int`:
- `Nat.gcd_left_comm`: `gcd m (gcd n k) = gcd n (gcd m k)`
- `Int.gcd_left_comm`: `gcd a (gcd b c) = gcd b (gcd a c)`
These lemmas establish the left-commutativity property for gcd,
complementing the existing `gcd_comm` and `gcd_assoc` lemmas.
Upstreamed from
https://github.com/leanprover-community/mathlib4/pull/33235🤖 Prepared with Claude Code
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
This PR adds a `with_unfolding_none` tactic that sets the transparency
mode to `.none`, in which no definitions are unfolded. This complements
the existing `with_unfolding_all` tactic and provides tactic-level
access to the `TransparencyMode.none` added in
https://github.com/leanprover/lean4/pull/11810.
🤖 Prepared with Claude Code
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
This PR changes the definition of the iterator combinators `takeWhileM`
and `dropWhileM` so that they use `MonadAttach`. This is only relevant
in rare cases, but makes it sometimes possible to prove such combinators
finite when the finiteness depends on properties of the monadic
predicate.
This PR makes the `FinitenessRelation` structure, which is helpful when
proving the finiteness of iterators, part of the public API. Previously,
it was marked internal and experimental.
This PR adds the attributes `[grind norm]` and `[grind unfold]` for
controlling the `grind` normalizer/preprocessor.
The `norm` modifier instructs `grind` to use a theorem as a
normalization rule. That is, the theorem is applied during the
preprocessing step. This feature is meant for advanced users who
understand how the preprocessor and `grind`'s search procedure interact
with each other.
New users can still benefit from this feature by restricting its use to
theorems that completely eliminate a symbol from the goal. Example:
```lean
theorem max_def : max n m = if n ≤ m then m else n
```
For a negative example, consider:
```lean
opaque f : Int → Int → Int → Int
theorem fax1 : f x 0 1 = 1 := sorry
theorem fax2 : f 1 x 1 = 1 := sorry
attribute [grind norm] fax1
attribute [grind =] fax2
example (h : c = 1) : f c 0 c = 1 := by
grind -- fails
```
In this example, `fax1` is a normalization rule, but it is not
applicable to the input goal since `f c 0 c` is not an instance of `f x
0 1`. However, `f c 0 c` matches the pattern `f 1 x 1` modulo the
equality `c = 1`. Thus, `grind` instantiates `fax2` with `x := 0`,
producing the equality `f 1 0 1 = 1`, which the normalizer simplifies to
`True`. As a result, nothing useful is learned. In the future, we plan
to include linters to automatically detect issues like these. Example:
```lean
opaque f : Nat → Nat
opaque g : Nat → Nat
@[grind norm] axiom fax : f x = x + 2
@[grind norm ←] axiom fg : f x = g x
example : f x ≥ 2 := by grind
example : f x ≥ g x := by grind
example : f x + g x ≥ 4 := by grind
```
The `unfold` modifier instructs `grind` to unfold the given definition
during the preprocessing step. Example:
```lean
@[grind unfold] def h (x : Nat) := 2 * x
example : 6 ∣ 3*h x := by grind
```
This PR fixes a mismatch between the behavior of `foldlM` and
`foldlMUnsafe` in the three array
types. This mismatch is only exposed when manually specifying a `stop`
value greater than the size
of the array and only exploitable through `native_decide`.
The mismatch was introduced as part of
4ba21ea10c which introduced
`foldlMUnsafe` and thus likely a mistake when building the `unsafe`
implementation instead of a
specification mistake.
Closes#11773
This PR implements user-defined `grind` attributes. They are useful for
users that want to implement tactics using the `grind` infrastructure
(e.g., `progress*` in Aeneas). New `grind` attributes are declared using
the command
```lean
register_grind_attr my_grind
```
The command is similar to `register_simp_attr`. After the new attribute
is declared. Recall that similar to `register_simp_attr`, the new
attribute cannot be used in the same file it is declared.
```lean
opaque f : Nat → Nat
opaque g : Nat → Nat
@[my_grind] theorem fax : f (f x) = f x := sorry
example theorem fax2 : f (f (f x)) = f x := by
fail_if_success grind
grind [my_grind]
```
TODO: remove leftovers after update stage0
This PR allows `grind` to use `List.eq_nil_of_length_eq_zero` (and
`Array.eq_empty_of_size_eq_zero`), but only when it has already proved
the length is zero.
This PR moves the grind pattern from `Sublist.eq_of_length` to the
slightly more general `Sublist.eq_of_length_le`, and adds a grind
pattern guard so it only activates if we have a proof of the hypothesis.
This PR introduces some additional lemmas around `BitVec.extractLsb'`
and `BitVec.extractLsb`.
---------
Co-authored-by: Tobias Grosser <github@grosser.es>
Co-authored-by: Tobias Grosser <tobias@grosser.es>
This PR renames the namespace `Std.Range` to `Std.Legacy.Range`. Instead
of using `Std.Range` and `[a:b]` notation, the new range type `Std.Rco`
and its corresponding `a...b` notation should be used. There are also
other ranges with open/closed/infinite boundary shapes in
`Std.Data.Range.Polymorphic` and the new range notation also works for
`Int`, `Int8`, `UInt8`, `Fin` etc.
This PR adds more MPL spec lemmas for all combinations of `for` loops,
`fold(M)` and the `filter(M)/filterMap(M)/map(M)` iterator combinators.
These kinds of loops over these combinators (e.g. `it.mapM`) are first
transformed into loops over their base iterators (`it`), and if the base
iterator is of type `Iter _` or `IterM Id _`, then another spec lemma
exists for proving Hoare triples about it using an invariant and the
underlying list (`it.toList`). The PR also fixes a bug that MPL always
assigns the default priority to spec lemmas if `Std.Tactic.Do.Syntax` is
not imported and a bug that low-priority lemmas are preferred about
high-priority ones.
For context, the MPL bug was related to the fact that the `Attr.spec`
syntax is not built-in. Therefore, Lean falls back to the `Attr.simple`
syntax, which *basically* also works, but which stores the priority at a
different position. The routine to extract the priority does not
consider this and so it falls back to the default priority given an
`Attr.simple` syntax object.
This PR improves the performance of autocompletion and fuzzy matching by
introducing an ASCII fast path into one of their core loops and making
Char.toLower/toUpper more efficient.
Co-authored-by: Rob23oba <152706811+Rob23oba@users.noreply.github.com>
This PR extends the get-elem tactic for ranges so that it supports
subarrays. Example:
```lean
example {a : Array Nat} (h : a.size = 28) : Id Unit := do
let mut x := 0
for h : i in *...(3 : Nat) do
x := a[1...4][i]
```
This PR provides many lemmas about `Int` ranges, in analogy to those
about `Nat` ranges. A few necessary basic `Int` lemmas are added. The PR
also removes `simp` annotations on `Rcc.toList_eq_toList_rco`,
`Nat.toList_rcc_eq_toList_rco` and consorts.
This PR adds the definition of `BitVec.cpop`, which relies on the more
general `BitVec.cpopNatRec`, and build some theory around it. The name
`cpop` aligns with the [RISCV ISA
nomenclature](https://msyksphinz-self.github.io/riscv-isadoc/#_cpop).
Co-authored-by: @tobiasgrosser, @bollu
---------
Co-authored-by: Tobias Grosser <tobias@grosser.es>
Co-authored-by: Tobias Grosser <github@grosser.es>
Co-authored-by: Siddharth <siddu.druid@gmail.com>
This PR makes it possible to verify loops over iterators. It provides
MPL spec lemmas about `for` loops over pure iterators. It also provides
spec lemmas that rewrite loops over `mapM`, `filterMapM` or `filterM`
iterator combinators into loops over their base iterator.
This PR refactors match compilation, to handle “side-effect free”
patterns (`.var`, `.inaccessible`, `.as`) eagerly and for each
alternative separately. The idea is that there should be less interplay
between different alternatives, and prepares the ground for #11105.
This may cause some corner case match statements to compiler or fail
compile that behaved differently before. For example, it can now use a
sparse case where previously was using a full case, and pattern
completeness may not be clear to lean now. On the other hand, using a
sparse case can mean that match statements mixing matching in indicies
with matching on the indexed datatype can work.
This PR adds the new operation `MonadAttach.attach` that attaches a
proof that a postcondition holds to the return value of a monadic
operation. Most non-CPS monads in the standard library support this
operation in a nontrivial way. The PR also changes the `filterMapM`,
`mapM` and `flatMapM` combinators so that they attach postconditions to
the user-provided monadic functions passed to them. This makes it
possible to prove termination for some of these for which it wasn't
possible before. Additionally, the PR adds many missing lemmas about
`filterMap(M)` and `map(M)` that were needed in the course of this PR.
This PR improves `match` generalization such that it abstracts
metavariables in types of local variables and in the result type of the
match over the match discriminants. Previously, a metavariable in the
result type would silently default to the behavior of `generalizing :=
false`, and a metavariable in the type of a free variable would lead to
an error (#8099). Example of a `match` that elaborates now but
previously wouldn't:
```lean
example (a : Nat) (ha : a = 37) :=
(match a with | 42 => by contradiction | n => n) = 37
```
This is because the result type of the `match` is a metavariable that
was not abstracted over `a` and hence generalization failed; the result
is that `contradiction` cannot pick up the proof `ha : 42 = 37`.
The old behavior can be recovered by passing `(generalizing := false)`
to the `match`.
Furthermore, programs such as the following can now be elaborated:
```lean
example (n : Nat) : Id (Fin (n + 1)) :=
have jp : ?m := ?rhs
match n with
| 0 => ?jmp1
| n + 1 => ?jmp2
where finally
case m => exact Fin (n + 1) → Id (Fin (n + 1))
case jmp1 => exact jp ⟨0, by decide⟩
case jmp2 => exact jp ⟨n, by omega⟩
case rhs => exact pure
```
This is useful for the `do` elaborator.
Fixes#8099.
This PR fixes the `grind` support for `Nat.ctorIdx`. Nat constructors
appear in `grind` as offsets or literals, and not as a node marked
`.constr`, so handle that case as well.
This PR moves many constants of the iterator API from `Std.Iterators` to
the `Std` namespace in order to make them more convenient to use. These
constants include, but are not limited to, `Iter`, `IterM` and
`IteratorLoop`. This is a breaking change. If something breaks, try
adding `open Std` in order to make these constants available again. If
some constants in the `Std.Iterators` namespace cannot be found, they
can be found directly in `Std` now.
This PR adds basic support for equality propagation in `grind linarith`
for the `IntModule` case. This covers only the basic case. See note in
the code.
We remark this feature is irrelevant for `CommRing` since `grind ring`
already has much better support for equality propagation.
This PR adds support for `Int.sign`, `Int.fdiv`, `Int.tdiv`, `Int.fmod`,
`Int.tmod`, and `Int.bmod` to `grind`. These operations are just
preprocessed away. We assume that they are not very common in practice.
Examples:
```lean
example {x y : Int} : y = 0 → (x.fdiv y) = 0 := by grind
example {x y : Int} : y = 0 → (x.tdiv y) = 0 := by grind
example {x y : Int} : y = 0 → (x.fmod y) = x := by grind
example {x y : Int} : y = 1 → (x.fdiv (2 - y)) = x := by grind
example {x : Int} : x > 0 → x.sign = 1 := by grind
example {x : Int} : x < 0 → x.sign = -1 := by grind
example {x y : Int} : x.sign = 0 → x*y = 0 := by grind
```
See #11622
This PR adds propagation rules corresponding to the `Semiring`
normalization rules introduced in #11628. The new rules apply only to
non-commutative semirings, since support for them in `grind` is limited.
The normalization rules introduced unexpected behavior in Mathlib
because they neutralize parameters such as `one_mul`: any theorem
instance associated with such a parameter is reduced to `True` by the
normalizer.
This PR teaches `grind` how to reduce `.ctorIdx` applied to
constructors. It can also handle tasks like
```
xs ≍ Vec.cons x xs' → xs.ctorIdx = 1
```
thanks to a `.ctorIdx.hinj` theorem (generated on demand).
This PR implements a linter that warns when a deprecated coercion is
applied. It also warns when the `Option` coercion or the
`Subarray`-to-`Array` coercion is used in `Init` or `Std`. The linter is
currently limited to `Coe` instances; `CoeFun` instances etc. are not
considered.
The linter works by collecting the `Coe` instance declaration names that
are being expanded in `expandCoe?` and storing them in the info tree.
The linter itself then analyzes the info tree and checks for banned or
deprecated coercions.
This PR adds `@[suggest_for ℤ]` on `Int` and `@[suggest_for ℚ]` on
`Rat`, following the pattern established by `@[suggest_for ℕ]` on `Nat`
in #11554.
🤖 Prepared with Claude Code
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>