Remove impl Deref for AnsiGenericString
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The `Deref` implementation for `AnsiGenericString` and its derived type aliases probably violates the tacit definition of the `Deref` trait" https://doc.rust-lang.org/std/ops/trait.Deref.html As the type aliases implement `Display` for the actual styling logic they get a blanket `impl ToString for T: Display + ?Sized` This has the nasty consequence that while you would expect that `fn foo(input: AsRef<str>)` would get the same input from `let styled: AnsiGenericString<_> = ...` for both `foo(styled)` and `foo(styled.to_string())` this doesn't hold. Thus the lint https://rust-lang.github.io/rust-clippy/master/index.html#unnecessary_to_owned will change the actual behavior and remove styling as the underlying string gets presented via `Deref`. This change removes the `Deref` implementation and fixes the internal uses.
Breaking change: remove deref implementation on the styled output `AnsiGenericString`
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Tested with nushell and reedline. Doesn't affect tests, builds pass, visual appearance is maintained. |
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sholderbach
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Jun 3, 2022
Resolves an unexpected issue due to `Deref` and `ToString` interacting Details: nushell/nu-ansi-term#5 and nushell/reedline#435 (comment) Also updates reedline: Includes a fix for a panic when the directory containing the history is deleted during a running reedline session. (nushell/reedline#436)
fennewald
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Jun 27, 2022
Resolves an unexpected issue due to `Deref` and `ToString` interacting Details: nushell/nu-ansi-term#5 and nushell/reedline#435 (comment) Also updates reedline: Includes a fix for a panic when the directory containing the history is deleted during a running reedline session. (nushell/reedline#436)
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The
Derefimplementation forAnsiGenericStringand its derived type aliases probably violates the tacit definition of theDereftrait:https://doc.rust-lang.org/std/ops/trait.Deref.html
As the type aliases implement
Displayfor the actual styling logic they get a blanketimpl ToString for T: Display + ?SizedThis has the nasty consequence that while you would expect that
fn foo(input: AsRef<str>)would get the same input fromlet styled: AnsiGenericString<_> = ...for bothfoo(styled)andfoo(styled.to_string())this doesn't hold.Thus the lint https://rust-lang.github.io/rust-clippy/master/index.html#unnecessary_to_owned will change the actual behavior and remove styling as the underlying string gets presented via
Deref.This change removes the
Derefimplementation and fixes the internal uses.