Fix issue with the error messages

Many of the errors where incorrectly showing "Required field is not
provided" when the field was provided but not valid.
This was raised by @ron on PR #3825

Author: heldersepu

src/core/utils.js

@@ -556,14 +556,19 @@ export const validateParam = (param, isXml, isOAS3 = false) => {
     Only bother validating the parameter if the type was specified.
   */
   if ( type && (required || value) ) {
-    // These checks should evaluate to true if the parameter's value is valid
-    let stringCheck = type === "string" && value && !validateString(value)
+    // These checks should evaluate to true if there is a parameter
+    let stringCheck = type === "string" && value
     let arrayCheck = type === "array" && Array.isArray(value) && value.length
     let listCheck = type === "array" && Im.List.isList(value) && value.count()
     let fileCheck = type === "file" && value instanceof win.File
-    let booleanCheck = type === "boolean" && !validateBoolean(value)
-    let numberCheck = type === "number" && !validateNumber(value) // validateNumber returns undefined if the value is a number
-    let integerCheck = type === "integer" && !validateInteger(value) // validateInteger returns undefined if the value is an integer
+    let booleanCheck = type === "boolean" && (value || value === false)
+    let numberCheck = type === "number" && value
+    let integerCheck = type === "integer" && value
+
+    if ( required && !(stringCheck || arrayCheck || listCheck || fileCheck || booleanCheck || numberCheck || integerCheck) ) {
+      errors.push("Required field is not provided")
+      return errors
+    }
 
     if (maxLength || maxLength === 0) {
       let err = validateMaxLength(value, maxLength)
@@ -575,11 +580,6 @@ export const validateParam = (param, isXml, isOAS3 = false) => {
       if (err) errors.push(err)
     }
 
-    if ( required && !(stringCheck || arrayCheck || listCheck || fileCheck || booleanCheck || numberCheck || integerCheck) ) {
-      errors.push("Required field is not provided")
-      return errors
-    }
-
     if (maximum || maximum === 0) {
       let err = validateMaximum(value, maximum)
       if (err) errors.push(err)

test/core/utils.js

@@ -524,7 +524,7 @@ describe("utils", function() {
         type: "boolean",
         value: "test string"
       }
-      assertValidateParam(param, ["Required field is not provided"])
+      assertValidateParam(param, ["Value must be a boolean"])
 
       // valid boolean value
       param = {
@@ -584,7 +584,7 @@ describe("utils", function() {
         type: "number",
         value: "test"
       }
-      assertValidateParam(param, ["Required field is not provided"])
+      assertValidateParam(param, ["Value must be a number"])
 
       // invalid number, undefined value
       param = {
@@ -666,7 +666,7 @@ describe("utils", function() {
         type: "integer",
         value: "test"
       }
-      assertValidateParam(param, ["Required field is not provided"])
+      assertValidateParam(param, ["Value must be an integer"])
 
       // invalid integer, undefined value
       param = {