small improvements

Author: edwindj

R/dnf.R

@@ -105,6 +105,8 @@ as_dnf <- function(expr, ...){
   clauses <- unlist(lapply(clauses, function(clause){
     if (op_to_s(clause) == "|"){
       as_dnf(clause)
+    } else if (op_to_s(clause) == "!"){
+      invert_or_negate(consume(left(clause)))
     } else{
       clause
     }

R/expr_manip.R

@@ -10,7 +10,11 @@ negate_ <- function(e, ...){
     if (op == "!="){
       substitute( l == r, list(l = left(e), r = right(e)))
     } else if (op == "=="){
-      substitute( l != r, list(l = left(e), r = right(e)))
+      if (is.logical(right(e))){
+        substitute( l == r, list(l = left(e), r = !right(e)))
+      } else {
+        substitute( l != r, list(l = left(e), r = right(e)))
+      }
     }
     else {
       substitute( !(e), list(e=e) )

tests/testthat/test-dnf.R

@@ -124,6 +124,24 @@ describe("as_dnf", {
     expect_equivalent(dnf, expression(x <= 1, z <= 1, w <= 1, y < 0))
   })
 
+  it("works on issue of negated linear consequent", {
+    dnf <- as_dnf(quote(if (A==TRUE) !x < 0))
+    expect_equivalent(as.expression(dnf), expression(A == FALSE | x >= 0))
+    
+    dnf <- as_dnf(quote(if (y > 0) !x < 0))
+    expect_equivalent(as.expression(dnf), expression(y <= 0 | x >= 0))
+    
+    dnf <- as_dnf(quote(if (!y > 0) !x < 0))
+    expect_equivalent(as.expression(dnf), expression(y > 0 | x >= 0))
+    
+    dnf <- as_dnf(quote(if (!y > 0) !x < 0 | z > 0))
+    expect_equivalent(as.expression(dnf), expression(y > 0 | x >= 0 | z > 0))
+    
+    dnf <- as_dnf(quote(if (!y > 0) !x < 0 | !z > 0))
+    expect_equivalent(as.expression(dnf), expression(y > 0 | x >= 0 | z <= 0))
+  })
+  
+  
 })