test: ignore unreachable guards from coverage

Author: ChALkeR

base58.js

@@ -207,7 +207,7 @@ function fromBase58core(str, alphabet, codes, format = 'uint8') {
       }
 
       at = k + 1
-      if (c !== 0 || at < zeros) throw new Error('Unexpected') // unreachable
+      if (c !== 0 || at < zeros) /* c8 ignore next */ throw new Error('Unexpected') // unreachable
     }
   }
 

fallback/_utils.js

@@ -47,6 +47,7 @@ function shouldSkipBuiltins() {
     return /firefox/i.test(g.navigator.userAgent || '') // as simple as we can
   }
 
+  /* c8 ignore next */
   return false // eslint-disable-line no-unreachable
 }
 

fallback/encoding.js

@@ -163,6 +163,7 @@ export class TextDecoder {
         return u.byteLength >= 2 && u[0] === 0xfe && u[1] === 0xff ? 2 : 0
     }
 
+    /* c8 ignore next */
     throw new Error('Unreachable')
   }
 }

fallback/multi-byte.js

@@ -791,7 +791,8 @@ export function multibyteEncoder(enc, onError) {
       throw new TypeError(E_STRICT)
     }
 
-    if (!map || map.length < size) throw new Error('Unreachable') // Important for perf
+    if (!map || map.length < size) /* c8 ignore next */ throw new Error('Unreachable') // Important for perf
+
     if (enc === 'gb18030') {
       // Deduping this branch hurts other encoders perf
       const encode = (cp) => {

fallback/utf8.js

@@ -191,7 +191,7 @@ export function encode(string, loose) {
 
     if (small) {
       // TODO: use resizable array buffers? will have to return a non-resizeable one
-      if (p !== i) throw new Error('Unreachable') // Here, p === i (only when small is still true)
+      if (p !== i) /* c8 ignore next */ throw new Error('Unreachable') // Here, p === i (only when small is still true)
       const bytesNew = new Uint8Array(p + (length - i) * 3) // maximium can be 3x of the string length in charcodes
       bytesNew.set(bytes)
       bytes = bytesNew

utf16.js

@@ -34,6 +34,7 @@ function encode(str, loose = false, format = 'uint16') {
 
   if (format === 'uint8-le' || format === 'uint8-be') return to8(u16) // Already swapped
   if (format === 'uint16') return u16
+  /* c8 ignore next */
   throw new Error('Unreachable')
 }
 

utf16.node.js

@@ -30,6 +30,7 @@ function encode(str, loose = false, format = 'uint16') {
     return new Uint16Array(b.buffer, b.byteOffset, b.byteLength / 2)
   }
 
+  /* c8 ignore next */
   throw new Error('Unreachable')
 }
 

utf32.js

@@ -19,6 +19,7 @@ function encode(str, loose = false, format = 'uint32') {
     return u8
   }
 
+  /* c8 ignore next */
   throw new Error('Unreachable')
 }