suppressed-errors

Suspicious

This rule is enabled as a warning by default.

What This Rule Does

Disallows suppressing or otherwise mishandling caught errors.

Functions that return error unions could error during "normal" execution. If they didn't, they would not return an error or would panic instead.

This rule enforces that errors are

1. Propagated up to callers either implicitly or by returning a new error,

   const a = try foo();
   const b = foo catch |e| {
       switch (e) {
           FooError.OutOfMemory => error.OutOfMemory,
           // ...
       }
   }

2. Are inspected and handled to continue normal execution

   /// It's fine if users are missing a config file, and open() + err
   // handling is faster than stat() then open()
   var config?: Config = openConfig() catch null;

3. Caught and paniced on to provide better crash diagnostics

   const str = try allocator.alloc(u8, size) catch @panic("Out of memory");

Examples

Examples of incorrect code for this rule:

const x = foo() catch {};
const y = foo() catch {
  // comments within empty catch blocks are still considered violations.
};
// `unreachable` is for code that will never be reached due to invariants.
const y = foo() catch unreachable

Examples of correct code for this rule:

const x = foo() catch @panic("foo failed.");
const y = foo() catch {
  std.debug.print("Foo failed.\n", .{});
};
const z = foo() catch null;
// Writer errors may be safely ignored
writer.print("{}", .{5}) catch {};

// suppression is allowed in tests
test foo {
  foo() catch {};
}

Configuration

This rule has no configuration.