Merge commit 'b52fb5234cd7c11ecfae51897a6f7fa52e8777fc' into clippyup

1 files changed, 32 insertions, 0 deletions

diff --git a/src/docs/recursive_format_impl.txt b/src/docs/recursive_format_impl.txt
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+++ b/src/docs/recursive_format_impl.txt
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+### What it does
+Checks for format trait implementations (e.g. `Display`) with a recursive call to itself
+which uses `self` as a parameter.
+This is typically done indirectly with the `write!` macro or with `to_string()`.
+
+### Why is this bad?
+This will lead to infinite recursion and a stack overflow.
+
+### Example
+
+```
+use std::fmt;
+
+struct Structure(i32);
+impl fmt::Display for Structure {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}", self.to_string())
+    }
+}
+
+```
+Use instead:
+```
+use std::fmt;
+
+struct Structure(i32);
+impl fmt::Display for Structure {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}", self.0)
+    }
+}
+```
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