Add leastArguments check

Author: git-ced

src/difference/index.ts

@@ -1,3 +1,5 @@
+import leastArguments from '../_utils/leastArguments';
+
 /**
  * @name difference
  * @summary Gets the difference.
@@ -43,9 +45,8 @@ export default function difference(
   const argLength = arguments.length;
   switch (argLength) {
     case 0:
-      return 0;
     case 1:
-      return a;
+      return leastArguments(2, argLength);
     case 2:
       return a - b;
     case 3:

src/mean/index.ts

@@ -1,3 +1,5 @@
+import leastArguments from '../_utils/leastArguments';
+
 /**
  * @name mean
  * @summary Gets the mean (average).
@@ -43,9 +45,8 @@ export default function mean(
   const argLength = arguments.length;
   switch (argLength) {
     case 0:
-      return 0;
     case 1:
-      return a;
+      return leastArguments(2, argLength);
     case 2:
       return (a + b) / 2;
     case 3:

src/product/index.ts

@@ -1,3 +1,5 @@
+import leastArguments from '../_utils/leastArguments';
+
 /**
  * @name product
  * @summary Gets the product.
@@ -43,9 +45,8 @@ export default function product(
   const argLength = arguments.length;
   switch (argLength) {
     case 0:
-      return 0;
     case 1:
-      return a;
+      return leastArguments(2, argLength);
     case 2:
       return a * b;
     case 3:

src/quotient/index.ts

@@ -1,3 +1,5 @@
+import leastArguments from '../_utils/leastArguments';
+
 /**
  * @name quotient
  * @summary Gets the quotient.
@@ -43,9 +45,8 @@ export default function quotient(
   const argLength = arguments.length;
   switch (argLength) {
     case 0:
-      return 0;
     case 1:
-      return a;
+      return leastArguments(2, argLength);
     case 2:
       return a / b;
     case 3:

src/remainder/index.ts

@@ -1,3 +1,5 @@
+import leastArguments from '../_utils/leastArguments';
+
 /**
  * @name remainder
  * @summary Gets the remainder.
@@ -43,9 +45,8 @@ export default function remainder(
   const argLength = arguments.length;
   switch (argLength) {
     case 0:
-      return 0;
     case 1:
-      return a;
+      return leastArguments(2, argLength);
     case 2:
       return a % b;
     case 3:

src/sum/index.ts

@@ -1,3 +1,5 @@
+import leastArguments from '../_utils/leastArguments';
+
 /**
  * @name sum
  * @summary Gets the sum.
@@ -43,9 +45,8 @@ export default function sum(
   const argLength = arguments.length;
   switch (argLength) {
     case 0:
-      return 0;
     case 1:
-      return a;
+      return leastArguments(2, argLength);
     case 2:
       return a + b;
     case 3: