added unit test for issue #56 for environment evaluation issues for M…

…PM models

tests/testthat/test-bas-lm.R

@@ -317,4 +317,29 @@ test_that("as.matrix tools", {
 })
 
 
+# GitHub issue #56 and #42 
+
+test_that("formula and env issues with MPM",{
+  data(UScrime, package = "MASS")
+  UScrime <- UScrime[, 1:5]
+
+  crime.bic1 <- bas.lm(formula = M ~ So + Ed + Po1 + Po2,
+                      data = UScrime,
+                      prior = "JZS",
+                      initprobs = c(1, 0.5, 0.5, 0.5, 0.5),
+                      renormalize = TRUE)
+    coef.mpm1 <- coef(crime.bic1, estimator = "MPM")
+
+    form <- M ~ So + Ed + Po1 + Po2
+    crime.bic2 <- BAS::bas.lm(formula = form,
+                              data = UScrime,
+                              prior = "JZS",
+                              initprobs = c(1, 0.5, 0.5, 0.5, 0.5),
+                              renormalize = TRUE)
+
+    expect_error(coef.mpm2 = coef(crime.bic2, estimator = "MPM"))
+   # expect_equal(coef.mpm1, coef.mpm2)
+  }  
+)
+