Nested macro bug

[zhouyx]

cc @ampproject/wg-analytics

In the following example, nested macro doesn't work properly

$REPLACE(CLIENT_ID(navigationStart)test, 'AD_', '')"
resolves to client_id, note that test is dropped

$REPLACE(testCLIENT_ID(navigationStart), 'AD_', '')"
resolves to test, note that client_id is dropped

$REPLACE(NAV_TIMING(navigationStart, loadEventStart), 'AD_', '')"
resolves to empty string, note that the nav_timing number is dropped.

I believe there are two issues here

1. Nested macro doesn't handle number properly
2. Nested macro doesn't handle concat string properly

[calebcordry]

:( Thanks for reporting.

[ampprojectbot]

This issue doesn't have a category which makes it harder for us to keep track of it. @calebcordry Please add an appropriate category.

[zhouyx]

Reported by @zikas :

I found the bug to be related to the issue here.

$IF(QUERY_PARAM(test), 1.$SUBSTR(TIMESTAMP, 0, 10)QUERY_PARAM(test), '')
resolve to 1.

and

$IF(QUERY_PARAM(gclid), $SUBSTR(TIMESTAMP, 0, 10)QUERY_PARAM(gclid), '')
resolve to 1234567890 (equals to $SUBSTR(TIMESTAMP,0,10)))