test(integration): coverage-driven SQL tests for under-exercised worker paths

test/sql/integration/scalar/function_registration.test

@@ -25,7 +25,7 @@ SELECT COUNT(*)
 FROM duckdb_functions()
 WHERE database_name = 'example' AND function_type = 'scalar';
 ----
-39
+41
 
 query T
 SELECT function_name
@@ -61,6 +61,8 @@ pair_type
 random_bytes
 random_int
 return_secret_value
+scale_by_setting
+secret_field
 smart_format
 smart_format
 sum_values
@@ -310,6 +312,30 @@ WHERE database_name = 'example' AND function_name = 'return_secret_value';
 ----
 return_secret_value	[]	[]	VARCHAR	CONSISTENT	Return a secret's value
 
+# ----------------------------------------------------------------------------
+# scale_by_setting — float Setting() parameter (read via get_f64, not visible)
+# Parameters: value (DOUBLE) → DOUBLE
+# ----------------------------------------------------------------------------
+
+query TTTTTT
+SELECT function_name, parameters, parameter_types, return_type, stability, description
+FROM duckdb_functions()
+WHERE database_name = 'example' AND function_name = 'scale_by_setting';
+----
+scale_by_setting	[value]	[DOUBLE]	DOUBLE	CONSISTENT	Scale the input value by the float setting `scale_factor`
+
+# ----------------------------------------------------------------------------
+# secret_field — Secret() parameter, looks up individual fields by name
+# Parameters: (none) → VARCHAR
+# ----------------------------------------------------------------------------
+
+query TTTTTT
+SELECT function_name, parameters, parameter_types, return_type, stability, description
+FROM duckdb_functions()
+WHERE database_name = 'example' AND function_name = 'secret_field';
+----
+secret_field	[]	[]	VARCHAR	CONSISTENT	Look up secret fields by name
+
 # ----------------------------------------------------------------------------
 # sum_values — Varargs with AnyArrow type and dynamic return type
 # Parameters: (none positional), varargs=ANY → ANY
@@ -358,7 +384,7 @@ SELECT COUNT(*)
 FROM duckdb_functions()
 WHERE database_name = 'example' AND function_type = 'scalar' AND varargs IS NULL;
 ----
-33
+35
 
 # ============================================================================
 # Stability
@@ -379,7 +405,7 @@ SELECT COUNT(*)
 FROM duckdb_functions()
 WHERE database_name = 'example' AND function_type = 'scalar' AND stability = 'CONSISTENT';
 ----
-37
+39
 
 # ============================================================================
 # Cleanup

test/sql/integration/scalar/numeric_promotion.test

@@ -0,0 +1,89 @@
+# name: test/sql/integration/scalar/numeric_promotion.test
+# description: Exercises numeric type promotion across float/unsigned/decimal/mixed-sign inputs
+# group: [vgi_integration_scalar]
+
+require-env VGI_TEST_WORKER
+
+require vgi
+
+require httpfs
+
+statement ok
+ATTACH 'example' AS example (TYPE vgi, LOCATION '${VGI_TEST_WORKER}');
+
+# ============================================================================
+# double(value) — output type is promoted for overflow headroom.
+# float32 -> float64 ; unsigned widens ; decimal gains one digit of precision.
+# ============================================================================
+
+query T
+SELECT typeof(example.double(1.5::REAL));
+----
+DOUBLE
+
+query I
+SELECT example.double(1.5::REAL) = 3.0;
+----
+true
+
+query T
+SELECT typeof(example.double(10::UTINYINT));
+----
+USMALLINT
+
+query I
+SELECT example.double(10::UTINYINT);
+----
+20
+
+query T
+SELECT typeof(example.double(100::UINTEGER));
+----
+UBIGINT
+
+query T
+SELECT typeof(example.double(1.25::DECIMAL(10,2)));
+----
+DECIMAL(11,2)
+
+query I
+SELECT example.double(1.25::DECIMAL(10,2)) = 2.50;
+----
+true
+
+# ============================================================================
+# add_values(a, b) — common numeric type of the two inputs, then promoted.
+# mixed-sign integers -> int64 ; same-sign widen ; decimals merge precision/scale.
+# ============================================================================
+
+query T
+SELECT typeof(example.add_values(2::INTEGER, 3::UINTEGER));
+----
+BIGINT
+
+query I
+SELECT example.add_values(2::INTEGER, 3::UINTEGER);
+----
+5
+
+query T
+SELECT typeof(example.add_values(2::TINYINT, 3::INTEGER));
+----
+BIGINT
+
+query I
+SELECT example.add_values(2::TINYINT, 3::INTEGER);
+----
+5
+
+# Decimal inputs exercise the decimal branch of the common-type computation. We
+# assert only the value, not typeof: the exact result precision/scale of decimal
+# addition is implementation-defined and differs between worker backends.
+
+query I
+SELECT example.add_values(1.50::DECIMAL(5,2), 2.250::DECIMAL(7,3)) = 3.750;
+----
+true
+
+statement ok
+DETACH example;

test/sql/integration/secret/secret_fields.test

@@ -0,0 +1,44 @@
+# name: test/sql/integration/secret/secret_fields.test
+# description: Exercises named/positional secret field accessors over a resolved secret
+# group: [vgi_integration_secret]
+
+require-env VGI_TEST_WORKER
+
+require vgi
+
+require httpfs
+
+statement ok
+ATTACH 'example' AS example (TYPE vgi, LOCATION '${VGI_TEST_WORKER}');
+
+# ============================================================================
+# secret_field() looks up a field on a named secret (named_field -> port) and
+# the first secret carrying a field of any name (field -> secret_string).
+# ============================================================================
+
+statement ok
+CREATE SECRET test_secret (TYPE vgi_example, secret_string 'hello_world', api_key 'key-abc-123', port 5432, use_ssl true, timeout 30.5);
+
+query T
+SELECT example.secret_field();
+----
+port=5432;name=hello_world
+
+# Re-create with different values — the accessors reflect the new secret.
+
+statement ok
+DROP SECRET test_secret;
+
+statement ok
+CREATE SECRET test_secret (TYPE vgi_example, secret_string 'rotated', api_key 'y', port 9999, use_ssl false, timeout 7.0);
+
+query T
+SELECT example.secret_field();
+----
+port=9999;name=rotated
+
+statement ok
+DROP SECRET test_secret;
+
+statement ok
+DETACH example;

test/sql/integration/settings/settings_types.test

@@ -0,0 +1,49 @@
+# name: test/sql/integration/settings/settings_types.test
+# description: Validates a float (DOUBLE) setting read via the get_f64 accessor
+# group: [vgi_integration_settings]
+
+require-env VGI_TEST_WORKER
+
+require vgi
+
+require httpfs
+
+statement ok
+ATTACH 'example' AS example (TYPE vgi, LOCATION '${VGI_TEST_WORKER}');
+
+# The float setting is registered and visible.
+
+query I
+SELECT COUNT(*) FROM duckdb_settings() WHERE name = 'scale_factor';
+----
+1
+
+# scale_by_setting(value) multiplies its input by the DOUBLE setting scale_factor,
+# read via Settings::get_f64.
+
+statement ok
+SET scale_factor = 2.5;
+
+query I
+SELECT example.scale_by_setting(4.0) = 10.0;
+----
+true
+
+query I
+SELECT example.scale_by_setting(value) = 5.0
+FROM (VALUES (2.0)) AS t(value);
+----
+true
+
+# A different float value is reflected on the next call.
+
+statement ok
+SET scale_factor = 0.5;
+
+query I
+SELECT example.scale_by_setting(10.0) = 5.0;
+----
+true
+
+statement ok
+DETACH example;

test/sql/integration/table/filtered_columns_pushdown.test

@@ -0,0 +1,69 @@
+# name: test/sql/integration/table/filtered_columns_pushdown.test
+# description: Pushed-filter column introspection — filtered_columns, has_filter_for_column, typed get_column_values_array
+# group: [vgi_integration_table]
+
+require-env VGI_TEST_WORKER
+
+require vgi
+
+require httpfs
+
+statement ok
+ATTACH 'example' AS example (TYPE vgi, LOCATION '${VGI_TEST_WORKER}');
+
+# filtered_columns_echo(count) reports, per query, which columns the pushed-down
+# filters reference (filtered_cols), whether a given column is filtered (has_n /
+# has_tag), and the discrete value set resolved for the string column `tag` via
+# the typed get_column_values_array accessor (tag_values).
+
+# No filter — nothing is constrained.
+
+query TTTT
+SELECT DISTINCT filtered_cols, has_n, has_tag, tag_values
+FROM example.filtered_columns_echo(5);
+----
+(empty)	false	false	(none)
+
+# Discrete IN on a string column — resolved as a typed value set.
+
+query TTTT
+SELECT DISTINCT filtered_cols, has_n, has_tag, tag_values
+FROM example.filtered_columns_echo(5) WHERE tag IN ('t1','t3');
+----
+tag	false	true	t1,t3
+
+# Equality on a string column.
+
+query TTTT
+SELECT DISTINCT filtered_cols, has_n, has_tag, tag_values
+FROM example.filtered_columns_echo(5) WHERE tag = 't2';
+----
+tag	false	true	t2
+
+# Both columns constrained (AND) — get_column_values_array digs into the AND child.
+
+query TTTT
+SELECT DISTINCT filtered_cols, has_n, has_tag, tag_values
+FROM example.filtered_columns_echo(5) WHERE n IN (1, 2, 3) AND tag = 't2';
+----
+n,tag	true	true	t2
+
+# A non-enumerable range filter — column is reported as filtered, but no discrete set.
+
+query TTTT
+SELECT DISTINCT filtered_cols, has_n, has_tag, tag_values
+FROM example.filtered_columns_echo(5) WHERE n >= 2;
+----
+n	true	false	(none)
+
+# The pushed filter is also applied to the rows (auto_apply_filters): the string
+# IN keeps exactly the matching rows.
+
+query IT
+SELECT n, tag FROM example.filtered_columns_echo(5) WHERE tag IN ('t1', 't3') ORDER BY n;
+----
+1	t1
+3	t3
+
+statement ok
+DETACH example;

test/sql/integration/table/function_registration.test

@@ -49,13 +49,15 @@ ATTACH 'example' AS example (TYPE vgi, LOCATION '${VGI_TEST_WORKER}');
 #   see table/time_travel_pushdown.test) +
 # 1 typed const-arg / typed-column emit fixture (typed_probe, see
 #   table/typed_probe.test)
-# = 93
+# 1 filter-column introspection fixture (filtered_columns_echo, see
+#   table/filtered_columns_pushdown.test)
+# = 94
 query I
 SELECT COUNT(*)
 FROM duckdb_functions()
 WHERE database_name = 'example' AND function_type = 'table';
 ----
-93
+94
 
 # The 33 pure table functions (no TABLE parameter type)
 # Note: make_series appears 5 times (5 overloads), make_pairs appears 3 times,