Solves #1535: Refactored prop_diff_cmh() and its helper functions

DESCRIPTION

@@ -20,6 +20,7 @@ Authors@R: c(
     person("Chendi", "Liao", role = "aut"),
     person("Jennifer", "Li", role = "aut"),
     person("David", "Munoz Tord", , "david.munoztord@mailbox.org", role = "ctb"),
+    person("Wojciech", "Wojciak", , "wojciech.wojciak@gmail.com", role = "ctb"),
     person("F. Hoffmann-La Roche AG", role = c("cph", "fnd"))
   )
 Description: Table, Listings, and Graphs (TLG) library for common outputs

NEWS.md

@@ -1,6 +1,13 @@
 # tern 0.9.12
 
 * Fixing CRAN release issue.
+* Fixed `prop_diff_cmh()` giving wrong Sato and Miettinen-Nurminen results when
+  some strata have only one group, and failing with a single stratum. (#1535)
+* `prop_diff_cmh()` returns `weights`, `n1` and `n2` for all strata now, with `NA`
+  weights for empty strata. It returns `NA` instead of `0` when no stratum has
+  both groups. (#1535)
+* `prop_cmh()` returns `NA` instead of `1` for the Sato p-value when the response
+  has no variation. (#1535)
 
 # tern 0.9.11