Adds new PError to CLI

Author: johnedquinn

partiql-cli/src/main/kotlin/org/partiql/cli/ErrorCodeString.kt

@@ -28,4 +28,5 @@ enum class ErrorCodeString(val code: Int) {
     NUMERIC_VALUE_OUT_OF_RANGE(PError.NUMERIC_VALUE_OUT_OF_RANGE),
     INVALID_CHAR_VALUE_FOR_CAST(PError.INVALID_CHAR_VALUE_FOR_CAST),
     DIVISION_BY_ZERO(PError.DIVISION_BY_ZERO),
+    DEGREE_VIOLATION_SCALAR_SUBQUERY(PError.DEGREE_VIOLATION_SCALAR_SUBQUERY)
 }

partiql-cli/src/main/kotlin/org/partiql/cli/pipeline/ErrorMessageFormatter.kt

@@ -34,6 +34,7 @@ object ErrorMessageFormatter {
             ErrorCodeString.INVALID_CHAR_VALUE_FOR_CAST -> invalidCharValueForCast(error)
             ErrorCodeString.DIVISION_BY_ZERO -> divisionByZero(error)
             ErrorCodeString.TYPE_UNEXPECTED -> typeUnexpected(error)
+            ErrorCodeString.DEGREE_VIOLATION_SCALAR_SUBQUERY -> degreeViolationScalarSubquery(error)
             ErrorCodeString.ALL -> "INTERNAL ERROR: This should never have occurred."
             null -> "Unrecognized error code received: ${error.code()}"
         }
@@ -129,6 +130,15 @@ object ErrorMessageFormatter {
         return "Cannot divide$dividendStr$dividendTypeStr by zero."
     }
 
+    /**
+     * @see PError.DEGREE_VIOLATION_SCALAR_SUBQUERY
+     */
+    private fun degreeViolationScalarSubquery(error: PError): String {
+        val actualType = error.getOrNull("ACTUAL", java.lang.Integer::class.java)
+        val actualTypeStr = prepare(actualType.toString(), " Actual degree: ", ".")
+        return "Degree of scalar subquery must be 1 (one).$actualTypeStr"
+    }
+
     /**
      * @see PError.TYPE_UNEXPECTED
      */
@@ -166,7 +176,7 @@ object ErrorMessageFormatter {
         val cause = error.getOrNull("CAUSE", Throwable::class.java)
         val writer = StringPrintWriter()
         writer.appendLine("Unexpected failure encountered. Caused by: $cause.")
-        cause.printStackTrace(writer)
+        cause?.printStackTrace(writer)
         return writer.w.sb.toString()
     }
 

partiql-spi/src/main/java/org/partiql/spi/errors/PError.java

@@ -169,6 +169,7 @@ public <T> List<T> getListOrNull(@NotNull String key, @NotNull Class<T> clazz) {
      * @return a property that may provide additional information about the error; {@code null} if the property does
      * not exist, or if the property cannot be cast to {@code clazz}.
      */
+    @Nullable
     public <T> T getOrNull(@NotNull String key, @NotNull Class<T> clazz) {
         try {
             return get(key, clazz);