Add documentation to source code

Author: Blargian

src/Functions/array/arrayJaccardIndex.cpp

@@ -151,7 +151,19 @@ class FunctionArrayJaccardIndex : public IFunction
 
 REGISTER_FUNCTION(ArrayJaccardIndex)
 {
-    factory.registerFunction<FunctionArrayJaccardIndex>();
+    FunctionDocumentation::Description description = "Returns the [Jaccard index](https://en.wikipedia.org/wiki/Jaccard_index) of two arrays.";
+    FunctionDocumentation::Syntax syntax = "arrayJaccardIndex(x, y)";
+    FunctionDocumentation::Arguments arguments = {
+        {"x", "First array. [Array](/sql-reference/data-types/array)."},
+        {"y", "Second array. [Array](/sql-reference/data-types/array)."},
+    };
+    FunctionDocumentation::ReturnedValue returned_value = "Returns the Jaccard index of `x` and `y`.[Float64](/sql-reference/data-types/float)";
+    FunctionDocumentation::Examples examples = {{"Usage example", "SELECT arrayJaccardIndex([1, 2], [2, 3]) AS res", "0.3333333333333333"}};
+    FunctionDocumentation::IntroducedIn introduced_in = {23, 7};
+    FunctionDocumentation::Category category = FunctionDocumentation::Category::Array;
+    FunctionDocumentation documentation = {description, syntax, arguments, returned_value, examples, introduced_in, category};
+
+    factory.registerFunction<FunctionArrayJaccardIndex>(documentation);
 }
 
 }

src/Functions/array/arrayReduce.cpp

@@ -216,7 +216,55 @@ ColumnPtr FunctionArrayReduce::executeImpl(const ColumnsWithTypeAndName & argume
 
 REGISTER_FUNCTION(ArrayReduce)
 {
-    factory.registerFunction<FunctionArrayReduce>();
+    FunctionDocumentation::Description description = R"(
+Applies an aggregate function to array elements and returns its result.
+The name of the aggregation function is passed as a string in single quotes `'max'`, `'sum'`.
+When using parametric aggregate functions, the parameter is indicated after the function name in parentheses `'uniqUpTo(6)'`.
+)";
+    FunctionDocumentation::Syntax syntax = "arrayReduce(agg_f, x1, x2, ..., xN)";
+    FunctionDocumentation::Arguments arguments = {
+        {"agg_f", "The name of an aggregate function which should be a constant [string](/sql-reference/data-types/string)."},
+        {"xN", "Any number of [array](/sql-reference/data-types/array) type columns as the parameters of the aggregation function."},
+    };
+    FunctionDocumentation::ReturnedValue returned_value = "Returns the result of the aggregate function";
+    FunctionDocumentation::Examples examples = {
+{"Usage example", "SELECT arrayReduce('max', [1, 2, 3]);",
+R"(
+┌─arrayReduce('max', [1, 2, 3])─┐
+│                             3 │
+└───────────────────────────────┘
+)"
+},
+{"Example with aggregate function using multiple arguments",
+R"(
+If an aggregate function takes multiple arguments, then this function must be applied to multiple arrays of the same size.
+
+```sql
+SELECT arrayReduce('maxIf', [3, 5], [1, 0]);
+```
+)",
+R"(
+┌─arrayReduce('maxIf', [3, 5], [1, 0])─┐
+│                                    3 │
+└──────────────────────────────────────┘
+)"
+},
+{"Example with a parametric aggregate function",
+R"(
+SELECT arrayReduce('uniqUpTo(3)', [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);
+)",
+R"(
+┌─arrayReduce('uniqUpTo(3)', [1, 2, 3, 4, 5, 6, 7, 8, 9, 10])─┐
+│                                                           4 │
+└─────────────────────────────────────────────────────────────┘
+)"
+}
+};
+    FunctionDocumentation::IntroducedIn introduced_in = {1, 1};
+    FunctionDocumentation::Category category = FunctionDocumentation::Category::Array;
+    FunctionDocumentation documentation = {description, syntax, arguments, returned_value, examples, introduced_in, category};
+
+    factory.registerFunction<FunctionArrayReduce>(documentation);
 }
 
 }

tests/queries/0_stateless/02415_all_new_functions_must_be_documented.reference

@@ -113,7 +113,6 @@ arrayFirstIndex
 arrayFirstOrNull
 arrayFlatten
 arrayIntersect
-arrayJaccardIndex
 arrayJoin
 arrayLast
 arrayLastIndex
@@ -128,7 +127,6 @@ arrayPushBack
 arrayPushFront
 arrayROCAUC
 arrayRandomSample
-arrayReduce
 arrayReduceInRanges
 arrayResize
 arrayReverse

tests/queries/0_stateless/02415_all_new_functions_must_have_version_information.reference

@@ -132,7 +132,6 @@ arrayFirstOrNull
 arrayFlatten
 arrayFold
 arrayIntersect
-arrayJaccardIndex
 arrayJoin
 arrayLast
 arrayLastIndex
@@ -152,7 +151,6 @@ arrayPushBack
 arrayPushFront
 arrayROCAUC
 arrayRandomSample
-arrayReduce
 arrayReduceInRanges
 arrayResize
 arrayReverse