5f4e6a86d5
This PR updates the formatting of, and adds explanations for, "unknown identifier" errors as well as "failed to infer type" errors for binders and definitions. It attempts to ameliorate some of the confusion encountered in #1592 by modifying the wording of the "header is elaborated before body is processed" note and adding further discussion and examples of this behavior in the corresponding error explanation.
123 lines
2.5 KiB
Text
123 lines
2.5 KiB
Text
/-!
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# Tests of the `sorry` term elaborator
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-/
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set_option pp.mvars false
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/-!
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Basic usage.
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-/
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/-- warning: declaration uses 'sorry' -/
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#guard_msgs in example : False := sorry
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/-- warning: declaration uses 'sorry' -/
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#guard_msgs in example : False := by sorry
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/-!
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Pretty printing
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-/
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/-- info: sorry : Nat -/
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#guard_msgs in #check (sorry : Nat)
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/-- info: fun x => sorry : Nat → Nat -/
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#guard_msgs in #check fun x : Nat => (sorry : Nat)
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/-- info: fun x => sorry (x + 1) : Nat → Nat -/
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#guard_msgs in #check fun x : Nat => (sorry : Nat → Nat) (x + 1)
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/-!
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Uniqueness
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-/
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/-- warning: declaration uses 'sorry' -/
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#guard_msgs in
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example : (sorry : Nat) = sorry := by
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fail_if_success rfl
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sorry
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/-- warning: declaration uses 'sorry' -/
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#guard_msgs in
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def f (n : Nat) : Nat → Nat := sorry
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example : f 0 0 = f 0 0 := rfl -- succeeds
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/-!
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If `sorry` is used for a function type, then one gets a family of unique `sorry`s.
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-/
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/--
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error: type mismatch
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rfl
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has type
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?_ = ?_
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but is expected to have type
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f 0 1 = f 0 0
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-/
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#guard_msgs in example : f 0 1 = f 0 0 := rfl
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/-!
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It is not completely unique though. The `sorry` did not pay attention to variables in the local context.
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-/
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#guard_msgs in example : f 1 0 = f 0 0 := rfl
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/-!
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Showing source position when surfacing differences.
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-/
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-- note: the module name is `sorry` and not `lean.run.sorry` in the testing environment,
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-- so this test fails in VS Code.
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/--
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error: type mismatch
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sorry
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has type
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sorry `«sorry:77:43»
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but is expected to have type
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sorry `«sorry:77:25»
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-/
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#guard_msgs in example : sorry := (sorry : sorry)
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/-!
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Elaboration errors are just labeled, not unique, to limit cascading errors.
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-/
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/--
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error: Unknown identifier `a`
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---
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error: Unknown identifier `b`
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---
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trace: ⊢ sorry = sorry
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-/
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#guard_msgs in
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set_option autoImplicit false in
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example : a = b := by trace_state; rfl
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/-!
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Showing that the sorries in the previous test are labeled.
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-/
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/--
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error: Unknown identifier `a`
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---
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error: Unknown identifier `b`
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---
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trace: ⊢ sorry `«sorry:106:10» = sorry `«sorry:106:14»
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-/
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#guard_msgs in
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set_option autoImplicit false in
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set_option pp.sorrySource true in
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example : a = b := by trace_state; rfl
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/-!
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The local context should show `sorry` without showing its source position.
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This requires `Lean.Widget.ppExprTagged` to have a pretty printing mode that doesn't override any pretty printing options.
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https://github.com/leanprover/lean4/issues/6715
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-/
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/--
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trace: n : Nat := sorry
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⊢ True
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---
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warning: declaration uses 'sorry'
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-/
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#guard_msgs in
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example : True := by
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let n : Nat := sorry
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trace_state
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trivial
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