Parse ConstantBytes in the parser

rebcabin · Jun 25, 2022 · 991e3a9 · 991e3a9
1 parent 4591db8
commit 991e3a9
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Showing 3 changed files with 17 additions and 2 deletions.
diff --git a/grammar/Python.asdl b/grammar/Python.asdl
@@ -85,6 +85,7 @@ module LPython
          | ConstantComplex(float re, float im, string? kind)
          | ConstantEllipsis(string? kind)
          | ConstantNone(string? kind)
+         | ConstantBytes(string value, string? kind)
 
          -- the following expression can appear in assignment context
          | Attribute(expr value, identifier attr, expr_context ctx)

diff --git a/src/lpython/parser/semantics.h b/src/lpython/parser/semantics.h
@@ -450,7 +450,9 @@ char* unescape(Allocator &al, LFortran::Str &s) {
 static inline ast_t *PREFIX_STRING(Allocator &al, Location &l, char *prefix, char *s){
     Vec<expr_t *> exprs;
     exprs.reserve(al, 4);
-    ast_t *tmp;
+    ast_t *tmp = nullptr;
+    // Assuming prefix has only one character.
+    prefix[0] = tolower(prefix[0]);
     if (strcmp(prefix, "f") == 0) {
         std::string str = std::string(s);
         std::string s1 = "\"";
@@ -494,8 +496,18 @@ static inline ast_t *PREFIX_STRING(Allocator &al, Location &l, char *prefix, cha
                 exprs.push_back(al, down_cast<expr_t>(tmp));
             }
         }
+        tmp = make_JoinedStr_t(al, l, exprs.p, exprs.size());
+    } else if (strcmp(prefix, "b") == 0) {
+        std::string str = std::string(s);
+        size_t start_pos = 0;
+        while((start_pos = str.find("\n", start_pos)) != std::string::npos) {
+                str.replace(start_pos, 1, "\\n");
+                start_pos += 2;
+        }
+        str = "b'" + str + "'";
+        tmp = make_ConstantBytes_t(al, l, LFortran::s2c(al, str), nullptr);
     }
-    return make_JoinedStr_t(al, l, exprs.p, exprs.size());
+    return tmp;
 }
 
 static inline keyword_t *CALL_KW(Allocator &al, Location &l,

diff --git a/src/runtime/lpython_parser.py b/src/runtime/lpython_parser.py
@@ -53,6 +53,8 @@ def visit_Constant(self, node):
             new_node = python_ast.ConstantEllipsis(node.kind)
         elif isinstance(node.value, None.__class__):
             new_node = python_ast.ConstantNone(node.kind)
+        elif isinstance(node.value, bytes):
+            new_node = python_ast.ConstantBytes(str(node.value), node.kind)
         else:
             print(type(node.value))
             raise Exception("Unsupported Constant type")