Add tests for R builds

test/testpkg/src/Makevars

@@ -0,0 +1,2 @@
+CXX_STD=CXX11
+PKG_LIBS=$(MAIN_LDFLAGS) $(LDFLAGS) $(LIBR) $(LIBS) $(LAPACK_LIBS) $(BLAS_LIBS) $(SHLIB_OPENMP_CFLAGS)

test/testpkg/src/add.c

@@ -0,0 +1,10 @@
+#include <R.h>
+#include <Rinternals.h>
+
+SEXP add(SEXP a, SEXP b)
+{
+  SEXP result = PROTECT(allocVector(REALSXP, 1));
+  REAL(result)[0] = asReal(a) + asReal(b);
+  UNPROTECT(1);
+  return result;
+}

test/testpkg/src/init.c

@@ -0,0 +1,33 @@
+#include <R.h>
+#include <Rinternals.h>
+#include <R_ext/Rdynload.h>
+
+#define CALLDEF(name, n)  {#name, (DL_FUNC) &name, n}
+#define FDEF(name)  {#name, (DL_FUNC) &F77_SUB(name), sizeof(name ## _t)/sizeof(name ## _t[0]), name ##_t}
+
+extern SEXP add(SEXP, SEXP);
+extern SEXP subtract(SEXP, SEXP);
+
+void F77_SUB(square)(int *n, int *answer);
+
+static R_NativePrimitiveArgType square_t[] = {
+    INTSXP,
+    INTSXP
+};
+
+static const R_CallMethodDef CallEntries[] = {
+    CALLDEF(add, 2),
+    CALLDEF(subtract, 2),
+    {NULL, NULL, 0}
+};
+
+static const R_FortranMethodDef fMethods[] = {
+    FDEF(square),
+    {NULL, NULL, 0}
+};
+
+void R_init_testpkg(DllInfo *dll)
+{
+    R_registerRoutines(dll, NULL, CallEntries, fMethods, NULL);
+    R_useDynamicSymbols(dll, FALSE);
+}

test/testpkg/src/square.f

@@ -0,0 +1,5 @@
+      subroutine square(x,answer)
+        integer, intent(in) :: x
+        integer, intent(out) :: answer
+        answer = x * x
+      end

test/testpkg/src/subtract.cpp

@@ -0,0 +1,10 @@
+#include <R.h>
+#include <Rinternals.h>
+
+extern "C" SEXP subtract(SEXP a, SEXP b)
+{
+  SEXP result = PROTECT(allocVector(REALSXP, 1));
+  REAL(result)[0] = asReal(a) - asReal(b);
+  UNPROTECT(1);
+  return result;
+}