`Debug` formatting floating point number does not (always) include decimal separator

[sanmai-NL]

In order to keep optimal equivalence between a Debug formatted representation of values and Rust source code, it would be helpful if e.g. f64 values are formatted including their decimal separator by default. This avoids having to adjust a whole lot of f64 fields in some larger structure when e.q. writing an equivalence assertion of such a value based on earlier Debug output. Currently, the values are formatted as integers when they are representable as integers.

Meta

rustc 1.25.0-nightly (79a521bb9 2018-01-15)
binary: rustc
commit-hash: 79a521bb9a8ace1a6663578a4c409906adde620d
commit-date: 2018-01-15
host: x86_64-unknown-linux-gnu
release: 1.25.0-nightly
LLVM version: 4.0

[varkor]

This seems to be the current behaviour as of 3e98f18. Are you sure you weren't using Display instead, or an older version of the compiler?

[dtolnay]

Thanks! This has been fixed as of #46831 and will be released in Rust 1.24.0.

[sanmai-NL]

@varkor: Yeah, I was using an older version of the compiler (different toolchain).