Incorrect string interpolation

Incorrect string interpolation occurs when placeholders or syntax used for injecting variables or expressions into strings are improperly structured or misused, resulting in incorrect, unintended, or literal outputs. This often happens due to mistakes in template literals (JavaScript), f-strings (Python), or other string formatting methods. Errors can include variables displaying as literal placeholders (e.g., ${variable}) rather than their intended values, concatenation issues, or incorrect formatting, all of which complicate debugging and produce unreliable outputs.

To fix incorrect string interpolation, verify correct syntax for the interpolation method used—for example, template literals (${variable} in JavaScript) or f-strings (f"{variable}" in Python)—ensuring proper formatting and variable injection. Replace incorrect concatenation or manual string joining with proper interpolation syntax for clarity and reliability. Utilize IDE features, linters, or static analyzers to detect and flag interpolation issues proactively. Regularly test string outputs thoroughly, especially in conditional or dynamic contexts, maintaining consistency and correctness in string generation throughout your codebase.