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no-print

Restriction
This rule is enabled as a warning by default.

What This Rule Does​

Disallows the use of std.debug.print.

print statements are great for debugging, but they should be removed before code gets merged. When you need debug logs in production, use std.log instead.

This rule makes a best-effort attempt to ensure print calls are actually from std.debug.print. It will not report calls to custom print functions if they are defined within the same file. If you are getting false positives because you import a custom print function, consider disabling this rule on a file-by-file basis instead of turning it off globally.

Tests​

By default, this rule ignores prints in test blocks and files. Files are considered to be a test file if they end with test.zig. You may disable this by setting allow_tests to false in the rule's metadata.

{
  "rules": {
    "no-print": ["warn", { "allow_tests": false }]
  }
}

Examples​

Examples of incorrect code for this rule:

const std = @import("std");
const debug = std.debug;
const print = std.debug.print;
fn main() void {
    std.debug.print("This should not be here: {d}\n", .{42});
    debug.print("This should not be here: {d}\n", .{42});
    print("This should not be here: {d}\n", .{42});
}

Examples of correct code for this rule:

const std = @import("std");
fn foo() u32 {
    std.log.debug("running foo", .{});
    return 1;
}

test foo {
    std.debug.print("testing foo\n", .{});
    try std.testing.expectEqual(1, foo());
}
fn print(comptime msg: []const u8, args: anytype) void {
    // ...
}
fn main() void {
    print("Staring program", .{});
}

Configuration​

This rule accepts the following options:

  • allow_tests: boolean