Add additional type checks

Author: DavisVaughan

src/main/envir.c

@@ -785,7 +785,12 @@ R_BindingType R_GetBindingType(SEXP sym, SEXP env) {
     // Ideally we'd do it once, which would require manually walking
     // over the environment frame / hashtable and get the location to
     // inspect.
-    
+
+    if (TYPEOF(sym) != SYMSXP)
+	error(_("not a symbol"));
+    if (TYPEOF(env) != ENVSXP)
+	error(_("not an environment"));
+
     // This check must be before `Rf_findVarInFrame3()` because that
     // forces active bindings
     if (R_BindingIsActive(sym, env))
@@ -3627,6 +3632,11 @@ attribute_hidden Rboolean R_HasFancyBindings(SEXP rho)
 
 // Equivalent to `substitute()`, but only supports promises
 SEXP R_DelayedBindingExpression(SEXP sym, SEXP env) {
+    if (TYPEOF(sym) != SYMSXP)
+	error(_("not a symbol"));
+    if (TYPEOF(env) != ENVSXP)
+	error(_("not an environment"));
+
     SEXP value = Rf_findVarInFrame3(env, sym, FALSE);
 
     if (TYPEOF(value) != PROMSXP)
@@ -3640,6 +3650,11 @@ SEXP R_DelayedBindingExpression(SEXP sym, SEXP env) {
 }
 
 SEXP R_DelayedBindingEnvironment(SEXP sym, SEXP env) {
+    if (TYPEOF(sym) != SYMSXP)
+	error(_("not a symbol"));
+    if (TYPEOF(env) != ENVSXP)
+	error(_("not an environment"));
+
     SEXP value = Rf_findVarInFrame3(env, sym, FALSE);
 
     if (TYPEOF(value) != PROMSXP)
@@ -3652,6 +3667,11 @@ SEXP R_DelayedBindingEnvironment(SEXP sym, SEXP env) {
 }
 
 SEXP R_ForcedBindingExpression(SEXP sym, SEXP env) {
+    if (TYPEOF(sym) != SYMSXP)
+	error(_("not a symbol"));
+    if (TYPEOF(env) != ENVSXP)
+	error(_("not an environment"));
+
     SEXP value = Rf_findVarInFrame3(env, sym, FALSE);
 
     if (TYPEOF(value) != PROMSXP)