feat: support current_utctimestamp (#865)

works locally with SAP HANA Cloud but does not work with HXE

---------

Co-authored-by: Samuel Brucksch <SamuelBrucksch@users.noreply.github.com>

hana/lib/cql-functions.js

@@ -107,6 +107,7 @@ const StandardFunctions = {
   current_date: () => 'current_utcdate',
   current_time: () => 'current_utctime',
   current_timestamp: () => 'current_utctimestamp',
+  current_utctimestamp: x => x ? `current_utctimestamp(${x})` : 'current_utctimestamp',
   fractionalseconds: x => `(TO_DECIMAL(SECOND(${x}),5,3) - TO_INTEGER(SECOND(${x})))`,
 }
 

hana/test/hana-functions.test.js

@@ -0,0 +1,50 @@
+const cds = require('../../test/cds')
+
+describe('HANA native functions', () => {
+  const { expect } = cds.test(__dirname, 'fuzzy.cds')
+
+  describe('current_timestamp', () => {
+    test('no arguments', async () => {
+      const cqn = { SELECT: {
+        one: true,
+        from: {ref: ['DUMMY']}, 
+        columns: [{func: 'current_utctimestamp', as: 'NO'}]
+      }}
+
+      const res = await cds.run(cqn)
+
+      expect(res.NO.match(/\.(\d\d\d)0000/)).not.to.be.null // default 3
+    })
+
+    // HXE does not allow args
+    test.skip('0 skips ms precision', async () => {
+      const cqn = { SELECT: {
+        one: true,
+        from: {ref: ['DUMMY']}, 
+        columns: [
+          {func: 'current_utctimestamp', as: 'NO'},
+          {func: 'current_utctimestamp', args: [{val: 0}], as: 'P0'}]
+      }}
+
+      const res = await cds.run(cqn)
+
+      expect(res.P0.match(/\.0000000/)).not.to.be.null
+    })
+
+    // HXE does not allow args
+    test.skip('arbitrary values', async () => {
+      const cqn = { SELECT: {
+        one: true,
+        from: {ref: ['DUMMY']}, 
+        columns: [
+          {func: 'current_utctimestamp', args: [{val: 3}], as: 'P3'},
+          {func: 'current_utctimestamp', args: [{val: 7}], as: 'P7'}] 
+      }}
+
+      const res = await cds.run(cqn)
+
+      expect(res.P3.match(/\.(\d\d\d)0000/)).not.to.be.null
+      expect(res.P7.match(/\.(\d\d\d\d\d\d\d)/)).not.to.be.null
+    })
+  })
+})