Add can and regex functions

src/main/java/com/bertramlabs/plugins/hcl4j/HCLBaseFunctions.java

@@ -98,6 +98,19 @@ static void registerBaseFunctions(HCLParser parser) {
             return null;
         });
 
+        parser.registerFunction("regex", (arguments) -> {
+            if(arguments.size() > 1 && arguments.get(0) != null ) {
+                String str = arguments.get(1) != null ? arguments.get(1).toString() : "";
+                Pattern regex = Pattern.compile(arguments.get(0).toString());
+                Matcher matcher = regex.matcher(str);
+                //convert match list to array of results
+                if(matcher.find()) {
+                    return matcher.group();
+                }
+            }
+            return null;
+        });
+
         parser.registerFunction("contains", (arguments) -> {
             if(arguments.size() == 2) {
                 if(arguments.get(0) instanceof Collection) {
@@ -136,7 +149,6 @@ static void registerBaseFunctions(HCLParser parser) {
                     } catch(ClassCastException ex) {
                         return null;
                     }
-
             } else {
                 return null; //Invalid Function Spec
             }
@@ -230,6 +242,16 @@ static void registerBaseFunctions(HCLParser parser) {
             return null;
         });
 
+        parser.registerFunction("can", (arguments) -> {
+            for(Object argument : arguments) {
+                if(argument != null) {
+                    return true;
+                }
+            }
+            return false;
+        });
+
+
         registerNumericFunctions(parser);
         registerCollectionFunctions(parser);
         registerDateFunctions(parser);
@@ -530,7 +552,7 @@ static void registerCastingFunctions(HCLParser parser) {
                     byte[] decodedBytes = Base64.getDecoder().decode(content);
                     return new String(decodedBytes,StandardCharsets.UTF_8);
                 }
-                
+
             }
             return null;
         });
@@ -556,7 +578,7 @@ static void registerCastingFunctions(HCLParser parser) {
                     byte[] decodedBytes = Base64.getDecoder().decode(content);
                     return new String(decodedBytes,Charset.forName(encoding));
                 }
-                
+
             }
             return null;
         });

src/test/groovy/com/bertramlabs/plugins/hcl4j/HCLParserSpec.groovy

@@ -392,7 +392,7 @@ default = ["subnet-72b9162b"]
  		def results = parser.parse(hcl)
  		then:
  		results.resource.aws_instance.test.tags.Date != null
- 		
+
 	}
 
 
@@ -1777,7 +1777,35 @@ variable "server_id" {
 
 	}
 
+	void "should parse can and regex"() {
+        given:
+        def hcl = '''
+variable "server_id" {
+    type        = string
+    description = "Server ID"
+    default 	= "abcabcabc"
+    validation {
+        condition = can(var.foo.boop)
+    }
+    validation {
+        condition = can(var.server_id)
+    }
+	validation {
+        condition = regex("ab", var.server_id)
+    }
+    validation {
+        condition = regexall("ab", var.server_id)
+    }
+  }'''
+        HCLParser parser = new HCLParser();
+        when:
+        def results = parser.parse(hcl)
+        then:
+        results.containsKey('variable')
+		results.variable.server_id.validation.size() == 4
+		results.variable.server_id.validation[0].condition == false
+		results.variable.server_id.validation[1].condition == true
+		results.variable.server_id.validation[2].condition == "ab"
+		results.variable.server_id.validation[3].condition == ["ab","ab","ab"]
+    }
 }
-
-
-