MB-70691: allow extractddl to filter functions by bucket

- When a bucket filter is specified, only return scoped functions
  belonging to that bucket; exclude global functions. Global functions
  are still included when no filter is specified.
- Strip surrounding backticks from the filter parameter so that
  backtick-quoted bucket names (e.g. `travel-sample`) are handled
  correctly.
- Update test files to add new test cases and modify previous ones.

Change-Id: I191c06aa1c940acf183fb564b6ecd68b0ef42e36
Reviewed-on: https://review.couchbase.org/c/query/+/241663
Well-Formed: Restriction Checker
Reviewed-by: Sitaram Vemulapalli <sitaram.vemulapalli@couchbase.com>
Tested-by: Sitaram Vemulapalli <sitaram.vemulapalli@couchbase.com>

Author: Sohoxic

expression/func_general.go

@@ -474,13 +474,24 @@ func (this *ExtractDDL) Evaluate(item value.Value, context Context) (value.Value
 		with = value.NewValue(map[string]interface{}{})
 	}
 
+	// Strip surrounding backticks from filter if present (e.g., '`travel-sample`' -> 'travel-sample')
+	filterSpecified := filter != nil && filter.ToString() != ""
+	if filterSpecified {
+		filterStr := strings.Trim(filter.ToString(), "`")
+		if filterStr != "" {
+			filter = value.NewValue(filterStr)
+		} else {
+			filterSpecified = false
+		}
+	}
+
 	res := make([]interface{}, 0, 32)
 	args := make(value.Values, 0, 1)
 
 	var buf strings.Builder
 	buf.Grow(128) // Pre-allocate buffer for the initial query
 	buf.WriteString("SELECT DISTINCT RAW name FROM system:keyspaces WHERE `namespace` = 'default' AND `bucket` IS NOT VALUED ")
-	if filter != nil && filter.ToString() != "" {
+	if filterSpecified {
 		buf.WriteString(" AND name LIKE ?")
 		args = append(args, filter)
 	}
@@ -544,8 +555,8 @@ func (this *ExtractDDL) Evaluate(item value.Value, context Context) (value.Value
 		}
 	}
 
-	// Extract global functions first (independent of buckets)
-	if flags&_FUNCTION_INFO != 0 {
+	// Extract global functions first (independent of buckets), but only when no specific bucket filter is specified
+	if flags&_FUNCTION_INFO != 0 && !filterSpecified {
 		stmt := "SELECT functions FROM system:functions " +
 			"WHERE functions.identity.type = 'global' " +
 			"ORDER BY functions.identity.name"

test/gsi/test_cases/extractddl/case_extractddl_basic.json

@@ -6,12 +6,6 @@
         "results": [
             {
                 "ddl_statements": [
-                    "CREATE OR REPLACE FUNCTION `add_numbers`(`a`, `b`) LANGUAGE INLINE AS a + b;",
-                    "CREATE OR REPLACE FUNCTION `ejs1`() LANGUAGE JAVASCRIPT AS \"ej1\" AT \"lib1\";",
-                    "CREATE OR REPLACE FUNCTION `no_param_func`() LANGUAGE INLINE AS 42;",
-                    "CREATE OR REPLACE FUNCTION `test_func`() LANGUAGE JAVASCRIPT AS \"function test_func() { return \"hello\"; }\";",
-                    "CREATE OR REPLACE FUNCTION `test_inline_func`(`x`) LANGUAGE INLINE AS x * 2;",
-                    "CREATE OR REPLACE FUNCTION `variadic_func`(...) LANGUAGE INLINE AS args[0] + args[1];",
                     "CREATE BUCKET `customer` WITH {'evictionPolicy':'fullEviction','numVBuckets':128,'ramQuota':250,'storageBackend':'magma'};",
                     "CREATE INDEX `test_index` ON `customer`(`name`) ;",
                     "CREATE SEQUENCE `default`:`customer`.`_default`.`test_sequence` START WITH 100 CACHE 10 NO CYCLE INCREMENT BY 5 MINVALUE -9223372036854775808;",
@@ -73,6 +67,18 @@
         "description": "Test ExtractDDL with function flag for customer bucket",
         "statements": "SELECT EXTRACTDDL('customer', {'flags': ['function']}) AS ddl_statements",
         "ordered": true,
+        "results": [
+            {
+                "ddl_statements": [
+                    "CREATE OR REPLACE FUNCTION `customer`.`_default`.`scoped_multiply`(`x`, `y`) LANGUAGE INLINE AS x * y;"
+                ]
+            }
+        ]
+    },
+    {
+        "description": "Test ExtractDDL with global scope for function flag",
+        "statements": "SELECT EXTRACTDDL('', {'flags': ['function']}) AS ddl_statements;",
+        "ordered": true,
         "results": [
             {
                 "ddl_statements": [