| // Copyright 2023 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| // Package stringintconv defines an Analyzer that flags type conversions |
| // from integers to strings. |
| // |
| // # Analyzer stringintconv |
| // |
| // stringintconv: check for string(int) conversions |
| // |
| // This checker flags conversions of the form string(x) where x is an integer |
| // (but not byte or rune) type. Such conversions are discouraged because they |
| // return the UTF-8 representation of the Unicode code point x, and not a decimal |
| // string representation of x as one might expect. Furthermore, if x denotes an |
| // invalid code point, the conversion cannot be statically rejected. |
| // |
| // As of Go 1.28, such conversions are rejected by the compiler in |
| // files whose Go version is go1.28 or later. |
| // |
| // The checker offers two fixes. The first, which is applied by "go |
| // fix", preserves the existing behavior by converting x to a rune |
| // first: string(rune(x)). If x may be wider than 32 bits, truncation |
| // to a rune could turn an invalid code point into a valid one, so |
| // the fix instead uses fmt.Sprintf("%c", x), which, like string(x), |
| // yields "\uFFFD" for all values outside the range of valid code |
| // points. |
| // |
| // The second fix formats the number as a decimal using |
| // fmt.Sprintf("%d", x), which is usually what was intended, |
| // but changes the behavior. |
| // |
| // To migrate a module to Go 1.28, run "go fix" before updating the |
| // go directive in its go.mod file, since after that, the package no |
| // longer compiles and cannot be analyzed. |
| package stringintconv |
