test(080): use deterministic test_date() function instead of CURRENT_DATE

Replace CURRENT_DATE with saga_repro.test_date() function that returns a
fixed date ('2026-01-01') for deterministic test output. This prevents
test failures due to date drift while still testing that DEFAULT values
are properly applied for columns not provided in the source data.

This follows the same pattern used in 052_view_current_basis.sql with
test_now() for testing current views.

Author: jhf

expected/080_temporal_merge_reported_regressions.out

@@ -28,6 +28,8 @@ GRANT CREATE ON SCHEMA public TO PUBLIC;
 \set ECHO all
 BEGIN;
 CREATE SCHEMA saga_repro;
+-- A stable function to override CURRENT_DATE for deterministic testing
+CREATE FUNCTION saga_repro.test_date() RETURNS date AS $$ SELECT '2026-01-01'::date $$ LANGUAGE sql;
 -- Base table definitions used by both scenarios
 CREATE TABLE saga_repro.target_units_template (
     unit_ident text NOT NULL,
@@ -895,7 +897,7 @@ CREATE TABLE saga_repro.target_with_audit (
     key_col TEXT NOT NULL,
     data_col TEXT,
     created_at TIMESTAMPTZ NOT NULL DEFAULT statement_timestamp(),
-    valid_from DATE NOT NULL DEFAULT CURRENT_DATE,
+    valid_from DATE NOT NULL DEFAULT saga_repro.test_date(),
     valid_until DATE NOT NULL DEFAULT 'infinity'::date,
     valid_range daterange NOT NULL,
     PRIMARY KEY (id, valid_range WITHOUT OVERLAPS)
@@ -921,7 +923,7 @@ CREATE TABLE saga_repro.source_without_audit (
     row_id INTEGER GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
     key_col TEXT NOT NULL,
     data_col TEXT,
-    valid_from DATE NOT NULL DEFAULT CURRENT_DATE,
+    valid_from DATE NOT NULL DEFAULT saga_repro.test_date(),
     valid_until DATE NOT NULL DEFAULT 'infinity'::date
 );
 INSERT INTO saga_repro.source_without_audit (key_col, data_col) VALUES ('test_key', 'test_data');
@@ -962,7 +964,7 @@ SELECT id, key_col, data_col, created_at IS NOT NULL as has_created_at, valid_fr
 FROM saga_repro.target_with_audit;
  id | key_col  | data_col  | has_created_at | valid_from | valid_until 
 ----+----------+-----------+----------------+------------+-------------
-  1 | test_key | test_data | t              | 2026-01-21 | infinity
+  1 | test_key | test_data | t              | 2026-01-01 | infinity
 (1 row)
 
 ROLLBACK TO SAVEPOINT scenario_ephemeral_missing_from_source;
@@ -983,7 +985,7 @@ CREATE TABLE saga_repro.target_with_audit_patch (
     key_col TEXT NOT NULL,
     data_col TEXT,
     created_at TIMESTAMPTZ NOT NULL DEFAULT statement_timestamp(),
-    valid_from DATE NOT NULL DEFAULT CURRENT_DATE,
+    valid_from DATE NOT NULL DEFAULT saga_repro.test_date(),
     valid_until DATE NOT NULL DEFAULT 'infinity'::date,
     valid_range daterange NOT NULL,
     PRIMARY KEY (id, valid_range WITHOUT OVERLAPS)
@@ -1009,7 +1011,7 @@ CREATE TABLE saga_repro.source_without_audit_patch (
     row_id INTEGER GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
     key_col TEXT NOT NULL,
     data_col TEXT,
-    valid_from DATE NOT NULL DEFAULT CURRENT_DATE,
+    valid_from DATE NOT NULL DEFAULT saga_repro.test_date(),
     valid_until DATE NOT NULL DEFAULT 'infinity'::date
 );
 INSERT INTO saga_repro.source_without_audit_patch (key_col, data_col) VALUES ('test_key_patch', 'test_data_patch');
@@ -1050,7 +1052,7 @@ SELECT id, key_col, data_col, created_at IS NOT NULL as has_created_at, valid_fr
 FROM saga_repro.target_with_audit_patch;
  id |    key_col     |    data_col     | has_created_at | valid_from | valid_until 
 ----+----------------+-----------------+----------------+------------+-------------
-  1 | test_key_patch | test_data_patch | t              | 2026-01-21 | infinity
+  1 | test_key_patch | test_data_patch | t              | 2026-01-01 | infinity
 (1 row)
 
 ROLLBACK TO SAVEPOINT scenario_ephemeral_missing_patch;
@@ -1079,7 +1081,7 @@ CREATE TABLE saga_repro.target_mixed_ephemeral (
     edit_by_user_id INTEGER NOT NULL,
     edit_at TIMESTAMPTZ NOT NULL DEFAULT statement_timestamp(),
     edit_comment TEXT,
-    valid_from DATE NOT NULL DEFAULT CURRENT_DATE,
+    valid_from DATE NOT NULL DEFAULT saga_repro.test_date(),
     valid_until DATE NOT NULL DEFAULT 'infinity'::date,
     valid_range daterange NOT NULL,
     PRIMARY KEY (id, valid_range WITHOUT OVERLAPS)
@@ -1111,7 +1113,7 @@ CREATE TABLE saga_repro.source_mixed_ephemeral (
     edit_by_user_id INTEGER NOT NULL,
     edit_at TIMESTAMPTZ NOT NULL,
     edit_comment TEXT,
-    valid_from DATE NOT NULL DEFAULT CURRENT_DATE,
+    valid_from DATE NOT NULL DEFAULT saga_repro.test_date(),
     valid_until DATE NOT NULL DEFAULT 'infinity'::date
 );
 INSERT INTO saga_repro.source_mixed_ephemeral 

sql/080_temporal_merge_reported_regressions.sql

@@ -9,6 +9,9 @@ BEGIN;
 
 CREATE SCHEMA saga_repro;
 
+-- A stable function to override CURRENT_DATE for deterministic testing
+CREATE FUNCTION saga_repro.test_date() RETURNS date AS $$ SELECT '2026-01-01'::date $$ LANGUAGE sql;
+
 -- Base table definitions used by both scenarios
 CREATE TABLE saga_repro.target_units_template (
     unit_ident text NOT NULL,
@@ -580,7 +583,7 @@ CREATE TABLE saga_repro.target_with_audit (
     key_col TEXT NOT NULL,
     data_col TEXT,
     created_at TIMESTAMPTZ NOT NULL DEFAULT statement_timestamp(),
-    valid_from DATE NOT NULL DEFAULT CURRENT_DATE,
+    valid_from DATE NOT NULL DEFAULT saga_repro.test_date(),
     valid_until DATE NOT NULL DEFAULT 'infinity'::date,
     valid_range daterange NOT NULL,
     PRIMARY KEY (id, valid_range WITHOUT OVERLAPS)
@@ -596,7 +599,7 @@ CREATE TABLE saga_repro.source_without_audit (
     row_id INTEGER GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
     key_col TEXT NOT NULL,
     data_col TEXT,
-    valid_from DATE NOT NULL DEFAULT CURRENT_DATE,
+    valid_from DATE NOT NULL DEFAULT saga_repro.test_date(),
     valid_until DATE NOT NULL DEFAULT 'infinity'::date
 );
 
@@ -652,7 +655,7 @@ CREATE TABLE saga_repro.target_with_audit_patch (
     key_col TEXT NOT NULL,
     data_col TEXT,
     created_at TIMESTAMPTZ NOT NULL DEFAULT statement_timestamp(),
-    valid_from DATE NOT NULL DEFAULT CURRENT_DATE,
+    valid_from DATE NOT NULL DEFAULT saga_repro.test_date(),
     valid_until DATE NOT NULL DEFAULT 'infinity'::date,
     valid_range daterange NOT NULL,
     PRIMARY KEY (id, valid_range WITHOUT OVERLAPS)
@@ -668,7 +671,7 @@ CREATE TABLE saga_repro.source_without_audit_patch (
     row_id INTEGER GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
     key_col TEXT NOT NULL,
     data_col TEXT,
-    valid_from DATE NOT NULL DEFAULT CURRENT_DATE,
+    valid_from DATE NOT NULL DEFAULT saga_repro.test_date(),
     valid_until DATE NOT NULL DEFAULT 'infinity'::date
 );
 
@@ -732,7 +735,7 @@ CREATE TABLE saga_repro.target_mixed_ephemeral (
     edit_by_user_id INTEGER NOT NULL,
     edit_at TIMESTAMPTZ NOT NULL DEFAULT statement_timestamp(),
     edit_comment TEXT,
-    valid_from DATE NOT NULL DEFAULT CURRENT_DATE,
+    valid_from DATE NOT NULL DEFAULT saga_repro.test_date(),
     valid_until DATE NOT NULL DEFAULT 'infinity'::date,
     valid_range daterange NOT NULL,
     PRIMARY KEY (id, valid_range WITHOUT OVERLAPS)
@@ -754,7 +757,7 @@ CREATE TABLE saga_repro.source_mixed_ephemeral (
     edit_by_user_id INTEGER NOT NULL,
     edit_at TIMESTAMPTZ NOT NULL,
     edit_comment TEXT,
-    valid_from DATE NOT NULL DEFAULT CURRENT_DATE,
+    valid_from DATE NOT NULL DEFAULT saga_repro.test_date(),
     valid_until DATE NOT NULL DEFAULT 'infinity'::date
 );