[ES|QL] Remove variadic functions' optional args from the output of show functions

docs/reference/esql/functions/types/case.asciidoc

@@ -4,6 +4,6 @@
 
 [%header.monospaced.styled,format=dsv,separator=|]
 |===
-condition | rest | result
+condition | value | result
 
 |===

docs/reference/esql/functions/types/concat.asciidoc

@@ -4,7 +4,7 @@
 
 [%header.monospaced.styled,format=dsv,separator=|]
 |===
-first | rest | result
+string1 | string2 | result
 keyword | keyword | keyword
 text | text | keyword
 |===

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/aggregate/Avg.java

@@ -26,7 +26,7 @@
 public class Avg extends AggregateFunction implements SurrogateExpression {
 
     @FunctionInfo(returnType = "double", description = "The average of a numeric field.", isAggregation = true)
-    public Avg(Source source, @Param(name = "field", type = { "double", "integer", "long" }) Expression field) {
+    public Avg(Source source, @Param(name = "number", type = { "double", "integer", "long" }) Expression field) {
         super(source, field);
     }
 

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/aggregate/Max.java

@@ -23,7 +23,7 @@
 public class Max extends NumericAggregate {
 
     @FunctionInfo(returnType = { "double", "integer", "long" }, description = "The maximum value of a numeric field.", isAggregation = true)
-    public Max(Source source, @Param(name = "field", type = { "double", "integer", "long" }) Expression field) {
+    public Max(Source source, @Param(name = "number", type = { "double", "integer", "long" }) Expression field) {
         super(source, field);
     }
 

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/aggregate/Median.java

@@ -31,7 +31,7 @@ public class Median extends AggregateFunction implements SurrogateExpression {
         description = "The value that is greater than half of all values and less than half of all values.",
         isAggregation = true
     )
-    public Median(Source source, @Param(name = "field", type = { "double", "integer", "long" }) Expression field) {
+    public Median(Source source, @Param(name = "number", type = { "double", "integer", "long" }) Expression field) {
         super(source, field);
     }
 

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/aggregate/MedianAbsoluteDeviation.java

@@ -27,7 +27,7 @@ public class MedianAbsoluteDeviation extends NumericAggregate {
         description = "The median absolute deviation, a measure of variability.",
         isAggregation = true
     )
-    public MedianAbsoluteDeviation(Source source, @Param(name = "field", type = { "double", "integer", "long" }) Expression field) {
+    public MedianAbsoluteDeviation(Source source, @Param(name = "number", type = { "double", "integer", "long" }) Expression field) {
         super(source, field);
     }
 

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/aggregate/Min.java

@@ -23,7 +23,7 @@
 public class Min extends NumericAggregate {
 
     @FunctionInfo(returnType = { "double", "integer", "long" }, description = "The minimum value of a numeric field.", isAggregation = true)
-    public Min(Source source, @Param(name = "field", type = { "double", "integer", "long" }) Expression field) {
+    public Min(Source source, @Param(name = "number", type = { "double", "integer", "long" }) Expression field) {
         super(source, field);
     }
 

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/aggregate/Percentile.java

@@ -36,7 +36,7 @@ public class Percentile extends NumericAggregate {
     )
     public Percentile(
         Source source,
-        @Param(name = "field", type = { "double", "integer", "long" }) Expression field,
+        @Param(name = "number", type = { "double", "integer", "long" }) Expression field,
         @Param(name = "percentile", type = { "double", "integer", "long" }) Expression percentile
     ) {
         super(source, field, List.of(percentile));

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/aggregate/Sum.java

@@ -29,7 +29,7 @@
 public class Sum extends NumericAggregate {
 
     @FunctionInfo(returnType = "long", description = "The sum of a numeric field.", isAggregation = true)
-    public Sum(Source source, @Param(name = "field", type = { "double", "integer", "long" }) Expression field) {
+    public Sum(Source source, @Param(name = "number", type = { "double", "integer", "long" }) Expression field) {
         super(source, field);
     }
 

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/conditional/Case.java

@@ -66,7 +66,7 @@ public Case(
         Source source,
         @Param(name = "condition", type = { "boolean" }) Expression first,
         @Param(
-            name = "rest",
+            name = "trueValue",
             type = {
                 "boolean",
                 "cartesian_point",

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/conditional/Greatest.java

@@ -43,7 +43,8 @@ public class Greatest extends EsqlScalarFunction implements OptionalArgument {
     public Greatest(
         Source source,
         @Param(name = "first", type = { "integer", "long", "double", "boolean", "keyword", "text", "ip", "version" }) Expression first,
-        @Param(name = "rest", type = { "integer", "long", "double", "boolean", "keyword", "text", "ip", "version" }) List<Expression> rest
+        @Param(name = "rest", type = { "integer", "long", "double", "boolean", "keyword", "text", "ip", "version" }, optional = true) List<
+            Expression> rest
     ) {
         super(source, Stream.concat(Stream.of(first), rest.stream()).toList());
     }

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/conditional/Least.java

@@ -43,7 +43,8 @@ public class Least extends EsqlScalarFunction implements OptionalArgument {
     public Least(
         Source source,
         @Param(name = "first", type = { "integer", "long", "double", "boolean", "keyword", "text", "ip", "version" }) Expression first,
-        @Param(name = "rest", type = { "integer", "long", "double", "boolean", "keyword", "text", "ip", "version" }) List<Expression> rest
+        @Param(name = "rest", type = { "integer", "long", "double", "boolean", "keyword", "text", "ip", "version" }, optional = true) List<
+            Expression> rest
     ) {
         super(source, Stream.concat(Stream.of(first), rest.stream()).toList());
     }

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/convert/ToBoolean.java

@@ -44,7 +44,7 @@ public class ToBoolean extends AbstractConvertFunction {
     @FunctionInfo(returnType = "boolean", description = "Converts an input value to a boolean value.")
     public ToBoolean(
         Source source,
-        @Param(name = "v", type = { "boolean", "keyword", "text", "double", "long", "unsigned_long", "integer" }) Expression field
+        @Param(name = "field", type = { "boolean", "keyword", "text", "double", "long", "unsigned_long", "integer" }) Expression field
     ) {
         super(source, field);
     }

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/convert/ToCartesianPoint.java

@@ -33,7 +33,7 @@ public class ToCartesianPoint extends AbstractConvertFunction {
     );
 
     @FunctionInfo(returnType = "cartesian_point", description = "Converts an input value to a point value.")
-    public ToCartesianPoint(Source source, @Param(name = "v", type = { "cartesian_point", "keyword", "text" }) Expression field) {
+    public ToCartesianPoint(Source source, @Param(name = "field", type = { "cartesian_point", "keyword", "text" }) Expression field) {
         super(source, field);
     }
 

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/convert/ToCartesianShape.java

@@ -37,7 +37,7 @@ public class ToCartesianShape extends AbstractConvertFunction {
     @FunctionInfo(returnType = "cartesian_shape", description = "Converts an input value to a shape value.")
     public ToCartesianShape(
         Source source,
-        @Param(name = "v", type = { "cartesian_point", "cartesian_shape", "keyword", "text" }) Expression field
+        @Param(name = "field", type = { "cartesian_point", "cartesian_shape", "keyword", "text" }) Expression field
     ) {
         super(source, field);
     }

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/convert/ToDatetime.java

@@ -43,7 +43,7 @@ public class ToDatetime extends AbstractConvertFunction {
     @FunctionInfo(returnType = "date", description = "Converts an input value to a date value.")
     public ToDatetime(
         Source source,
-        @Param(name = "v", type = { "date", "keyword", "text", "double", "long", "unsigned_long", "integer" }) Expression field
+        @Param(name = "field", type = { "date", "keyword", "text", "double", "long", "unsigned_long", "integer" }) Expression field
     ) {
         super(source, field);
     }

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/convert/ToDegrees.java

@@ -41,7 +41,7 @@ public class ToDegrees extends AbstractConvertFunction implements EvaluatorMappe
     );
 
     @FunctionInfo(returnType = "double", description = "Converts a number in radians to degrees.")
-    public ToDegrees(Source source, @Param(name = "v", type = { "double", "integer", "long", "unsigned_long" }) Expression field) {
+    public ToDegrees(Source source, @Param(name = "number", type = { "double", "integer", "long", "unsigned_long" }) Expression field) {
         super(source, field);
     }
 

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/convert/ToDouble.java

@@ -45,7 +45,10 @@ public class ToDouble extends AbstractConvertFunction {
     @FunctionInfo(returnType = "double", description = "Converts an input value to a double value.")
     public ToDouble(
         Source source,
-        @Param(name = "v", type = { "boolean", "date", "keyword", "text", "double", "long", "unsigned_long", "integer" }) Expression field
+        @Param(
+            name = "field",
+            type = { "boolean", "date", "keyword", "text", "double", "long", "unsigned_long", "integer" }
+        ) Expression field
     ) {
         super(source, field);
     }

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/convert/ToGeoPoint.java

@@ -33,7 +33,7 @@ public class ToGeoPoint extends AbstractConvertFunction {
     );
 
     @FunctionInfo(returnType = "geo_point", description = "Converts an input value to a geo_point value.")
-    public ToGeoPoint(Source source, @Param(name = "v", type = { "geo_point", "keyword", "text" }) Expression field) {
+    public ToGeoPoint(Source source, @Param(name = "field", type = { "geo_point", "keyword", "text" }) Expression field) {
         super(source, field);
     }
 

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/convert/ToGeoShape.java

@@ -35,7 +35,7 @@ public class ToGeoShape extends AbstractConvertFunction {
     );
 
     @FunctionInfo(returnType = "geo_shape", description = "Converts an input value to a geo_shape value.")
-    public ToGeoShape(Source source, @Param(name = "v", type = { "geo_point", "geo_shape", "keyword", "text" }) Expression field) {
+    public ToGeoShape(Source source, @Param(name = "field", type = { "geo_point", "geo_shape", "keyword", "text" }) Expression field) {
         super(source, field);
     }
 

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/convert/ToIP.java

@@ -33,7 +33,7 @@ public class ToIP extends AbstractConvertFunction {
     );
 
     @FunctionInfo(returnType = "ip", description = "Converts an input string to an IP value.")
-    public ToIP(Source source, @Param(name = "v", type = { "ip", "keyword", "text" }) Expression field) {
+    public ToIP(Source source, @Param(name = "field", type = { "ip", "keyword", "text" }) Expression field) {
         super(source, field);
     }
 

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/convert/ToInteger.java

@@ -47,7 +47,10 @@ public class ToInteger extends AbstractConvertFunction {
     @FunctionInfo(returnType = "integer", description = "Converts an input value to an integer value.")
     public ToInteger(
         Source source,
-        @Param(name = "v", type = { "boolean", "date", "keyword", "text", "double", "long", "unsigned_long", "integer" }) Expression field
+        @Param(
+            name = "field",
+            type = { "boolean", "date", "keyword", "text", "double", "long", "unsigned_long", "integer" }
+        ) Expression field
     ) {
         super(source, field);
     }

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/convert/ToLong.java

@@ -48,7 +48,10 @@ public class ToLong extends AbstractConvertFunction {
     @FunctionInfo(returnType = "long", description = "Converts an input value to a long value.")
     public ToLong(
         Source source,
-        @Param(name = "v", type = { "boolean", "date", "keyword", "text", "double", "long", "unsigned_long", "integer" }) Expression field
+        @Param(
+            name = "field",
+            type = { "boolean", "date", "keyword", "text", "double", "long", "unsigned_long", "integer" }
+        ) Expression field
     ) {
         super(source, field);
     }

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/convert/ToRadians.java

@@ -40,7 +40,7 @@ public class ToRadians extends AbstractConvertFunction implements EvaluatorMappe
     );
 
     @FunctionInfo(returnType = "double", description = "Converts a number in degrees to radians.")
-    public ToRadians(Source source, @Param(name = "v", type = { "double", "integer", "long", "unsigned_long" }) Expression field) {
+    public ToRadians(Source source, @Param(name = "number", type = { "double", "integer", "long", "unsigned_long" }) Expression field) {
         super(source, field);
     }
 

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/convert/ToString.java

@@ -64,7 +64,7 @@ public class ToString extends AbstractConvertFunction implements EvaluatorMapper
     public ToString(
         Source source,
         @Param(
-            name = "v",
+            name = "field",
             type = {
                 "boolean",
                 "cartesian_point",

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/convert/ToUnsignedLong.java

@@ -49,7 +49,10 @@ public class ToUnsignedLong extends AbstractConvertFunction {
     @FunctionInfo(returnType = "unsigned_long", description = "Converts an input value to an unsigned long value.")
     public ToUnsignedLong(
         Source source,
-        @Param(name = "v", type = { "boolean", "date", "keyword", "text", "double", "long", "unsigned_long", "integer" }) Expression field
+        @Param(
+            name = "field",
+            type = { "boolean", "date", "keyword", "text", "double", "long", "unsigned_long", "integer" }
+        ) Expression field
     ) {
         super(source, field);
     }

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/convert/ToVersion.java

@@ -33,7 +33,7 @@ public class ToVersion extends AbstractConvertFunction {
     );
 
     @FunctionInfo(returnType = "version", description = "Converts an input string to a version value.")
-    public ToVersion(Source source, @Param(name = "v", type = { "keyword", "text", "version" }) Expression v) {
+    public ToVersion(Source source, @Param(name = "field", type = { "keyword", "text", "version" }) Expression v) {
         super(source, v);
     }
 

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/date/DateExtract.java

@@ -43,14 +43,14 @@ public DateExtract(
         Source source,
         // Need to replace the commas in the description here with semi-colon as there's a bug in the CSV parser
         // used in the CSVTests and fixing it is not trivial
-        @Param(name = "date_part", type = { "keyword" }, description = """
+        @Param(name = "datePart", type = { "keyword" }, description = """
             Part of the date to extract.
             Can be: aligned_day_of_week_in_month; aligned_day_of_week_in_year; aligned_week_of_month;
             aligned_week_of_year; ampm_of_day; clock_hour_of_ampm; clock_hour_of_day; day_of_month; day_of_week;
             day_of_year; epoch_day; era; hour_of_ampm; hour_of_day; instant_seconds; micro_of_day; micro_of_second;
             milli_of_day; milli_of_second; minute_of_day; minute_of_hour; month_of_year; nano_of_day; nano_of_second;
             offset_seconds; proleptic_month; second_of_day; second_of_minute; year; or year_of_era.""") Expression chronoFieldExp,
-        @Param(name = "field", type = "date", description = "Date expression") Expression field,
+        @Param(name = "date", type = "date", description = "Date expression") Expression field,
         Configuration configuration
     ) {
         super(source, List.of(chronoFieldExp, field), configuration);

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/date/DateFormat.java

@@ -42,7 +42,7 @@ public class DateFormat extends EsqlConfigurationFunction implements OptionalArg
     @FunctionInfo(returnType = "keyword", description = "Returns a string representation of a date, in the provided format.")
     public DateFormat(
         Source source,
-        @Param(optional = true, name = "format", type = { "keyword" }, description = "A valid date pattern") Expression format,
+        @Param(optional = true, name = "dateFormat", type = { "keyword" }, description = "A valid date pattern") Expression format,
         @Param(name = "date", type = { "date" }, description = "Date expression") Expression date,
         Configuration configuration
     ) {

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/math/Abs.java

@@ -23,7 +23,7 @@
 
 public class Abs extends UnaryScalarFunction {
     @FunctionInfo(returnType = { "double", "integer", "long", "unsigned_long" }, description = "Returns the absolute value.")
-    public Abs(Source source, @Param(name = "n", type = { "double", "integer", "long", "unsigned_long" }) Expression n) {
+    public Abs(Source source, @Param(name = "number", type = { "double", "integer", "long", "unsigned_long" }) Expression n) {
         super(source, n);
     }
 

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/math/Acos.java

@@ -24,7 +24,11 @@ public class Acos extends AbstractTrigonometricFunction {
     @FunctionInfo(returnType = "double", description = "The arccosine of an angle, expressed in radians.")
     public Acos(
         Source source,
-        @Param(name = "n", type = { "double", "integer", "long", "unsigned_long" }, description = "Number between -1 and 1") Expression n
+        @Param(
+            name = "number",
+            type = { "double", "integer", "long", "unsigned_long" },
+            description = "Number between -1 and 1"
+        ) Expression n
     ) {
         super(source, n);
     }

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/math/Asin.java

@@ -24,7 +24,11 @@ public class Asin extends AbstractTrigonometricFunction {
     @FunctionInfo(returnType = "double", description = "Inverse sine trigonometric function.")
     public Asin(
         Source source,
-        @Param(name = "n", type = { "double", "integer", "long", "unsigned_long" }, description = "Number between -1 and 1") Expression n
+        @Param(
+            name = "number",
+            type = { "double", "integer", "long", "unsigned_long" },
+            description = "Number between -1 and 1"
+        ) Expression n
     ) {
         super(source, n);
     }

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/math/Atan.java

@@ -24,7 +24,7 @@ public class Atan extends AbstractTrigonometricFunction {
     @FunctionInfo(returnType = "double", description = "Inverse tangent trigonometric function.")
     public Atan(
         Source source,
-        @Param(name = "n", type = { "double", "integer", "long", "unsigned_long" }, description = "A number") Expression n
+        @Param(name = "number", type = { "double", "integer", "long", "unsigned_long" }, description = "A number") Expression n
     ) {
         super(source, n);
     }

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/math/Atan2.java

@@ -38,8 +38,8 @@ public class Atan2 extends EsqlScalarFunction {
     )
     public Atan2(
         Source source,
-        @Param(name = "y", type = { "double", "integer", "long", "unsigned_long" }, description = "y coordinate") Expression y,
-        @Param(name = "x", type = { "double", "integer", "long", "unsigned_long" }, description = "x coordinate") Expression x
+        @Param(name = "y_coordinate", type = { "double", "integer", "long", "unsigned_long" }, description = "y coordinate") Expression y,
+        @Param(name = "x_coordinate", type = { "double", "integer", "long", "unsigned_long" }, description = "x coordinate") Expression x
     ) {
         super(source, List.of(y, x));
         this.y = y;