From db45db76cd9c244e2261f0990a1efa27dcaaefbe Mon Sep 17 00:00:00 2001
From: Lukas Eder <lukas.eder@gmail.com>
Date: Mon, 23 Nov 2020 11:31:54 +0100
Subject: [PATCH] [jOOQ/jOOQ#11009] Add support for the MySQL FIELD() function

---
 jOOQ/src/main/java/org/jooq/impl/DSL.java     | 20 ++++++++++++++++
 jOOQ/src/main/java/org/jooq/impl/Names.java   |  1 +
 .../main/java/org/jooq/impl/ParserImpl.java   | 24 ++++---------------
 jOOQ/src/main/java/org/jooq/impl/Tools.java   | 12 ++++++++++
 4 files changed, 37 insertions(+), 20 deletions(-)

diff --git a/jOOQ/src/main/java/org/jooq/impl/DSL.java b/jOOQ/src/main/java/org/jooq/impl/DSL.java
index 1b569a71dc..351e406ae6 100644
--- a/jOOQ/src/main/java/org/jooq/impl/DSL.java
+++ b/jOOQ/src/main/java/org/jooq/impl/DSL.java
@@ -13490,6 +13490,26 @@ public class DSL {
     // XXX Global Field and Function factory
     // -------------------------------------------------------------------------
 
+    /**
+     * Get the MySQL <code>FIELD(expr, expr1, expr2, ...)</code> function.
+     */
+    @NotNull
+    @Support
+    @SafeVarargs
+    public static <T> Field<Integer> field(Field<T> field, T... list) {
+        return field(field, Tools.fieldsArray(list, field.getDataType()));
+    }
+
+    /**
+     * Get the MySQL <code>FIELD(expr, expr1, expr2, ...)</code> function.
+     */
+    @NotNull
+    @Support
+    @SafeVarargs
+    public static <T> Field<Integer> field(Field<T> field, Field<T>... list) {
+        return new FieldFunction<>(field, list);
+    }
+
     /**
      * Wrap a {@link SelectField} in a general-purpose {@link Field}
      */
diff --git a/jOOQ/src/main/java/org/jooq/impl/Names.java b/jOOQ/src/main/java/org/jooq/impl/Names.java
index 2c967b33a8..23ba503af6 100644
--- a/jOOQ/src/main/java/org/jooq/impl/Names.java
+++ b/jOOQ/src/main/java/org/jooq/impl/Names.java
@@ -114,6 +114,7 @@ final class Names {
     static final Name N_EXP                    = unquotedName("exp");
     static final Name N_EXTRACT                = unquotedName("extract");
     static final Name N_EXTRACT_DURATION       = unquotedName("extract_duration");
+    static final Name N_FIELD                  = unquotedName("field");
     static final Name N_FLASHBACK              = unquotedName("flashback");
     static final Name N_FLOOR                  = unquotedName("floor");
     static final Name N_FUNCTION               = unquotedName("function");
diff --git a/jOOQ/src/main/java/org/jooq/impl/ParserImpl.java b/jOOQ/src/main/java/org/jooq/impl/ParserImpl.java
index 1279693dd0..8d82c60f0c 100644
--- a/jOOQ/src/main/java/org/jooq/impl/ParserImpl.java
+++ b/jOOQ/src/main/java/org/jooq/impl/ParserImpl.java
@@ -9347,31 +9347,15 @@ final class ParserImpl implements Parser {
         return null;
     }
 
-    private static final <T, Z> Field<?> parseFieldFieldIf(ParserContext ctx) {
+    private static final <T> Field<?> parseFieldFieldIf(ParserContext ctx) {
         if (parseFunctionNameIf(ctx, "FIELD")) {
             parse(ctx, '(');
-
-            List<Field<?>> args = new ArrayList<>();
-
-            args.add(parseField(ctx));
+            Field<?> f1 = parseField(ctx);
             parse(ctx, ',');
-
-            int i = 1;
-            do {
-                args.add(parseField(ctx));
-                args.add(inline(i++));
-            }
-            while (parseIf(ctx, ','));
-
-            args.add(inline(0));
+            List<Field<?>> f2 = parseFields(ctx);
             parse(ctx, ')');
 
-            return DSL.decode(
-                (Field<T>) args.get(0),
-                (Field<T>) args.get(1),
-                (Field<Z>) args.get(2),
-                args.subList(3, args.size()).toArray(EMPTY_FIELD)
-            );
+            return DSL.field((Field<T>) f1, (Field<T>[]) f2.toArray(EMPTY_FIELD));
         }
 
         return null;
diff --git a/jOOQ/src/main/java/org/jooq/impl/Tools.java b/jOOQ/src/main/java/org/jooq/impl/Tools.java
index 01f4199328..80d0461256 100644
--- a/jOOQ/src/main/java/org/jooq/impl/Tools.java
+++ b/jOOQ/src/main/java/org/jooq/impl/Tools.java
@@ -1968,6 +1968,18 @@ final class Tools {
         return result;
     }
 
+    @SuppressWarnings("unchecked")
+    static final <T> Field<T>[] fieldsArray(Object[] values, DataType<T> type) {
+        if (values == null)
+            return (Field<T>[]) EMPTY_FIELD;
+
+        Field<T>[] result = new Field[values.length];
+        for (int i = 0; i < result.length; i++)
+            result[i] = field(values[i], type);
+
+        return result;
+    }
+
     static final Field<?>[] fieldsArray(Object[] values, DataType<?>[] types) {
         if (values == null || types == null)
             return EMPTY_FIELD;