Recognize literal encoding-prefixes also in the brace-match to find end of a top-level Cpp2 declaration

Closes #1142

Author: hsutter

regression-tests/test-results/version

@@ -1,5 +1,5 @@
 
-cppfront compiler v0.7.0   Build 9712:0834
+cppfront compiler v0.7.0   Build 9712:0914
 Copyright(c) Herb Sutter   All rights reserved
 
 SPDX-License-Identifier: CC-BY-NC-ND-4.0

source/build.info

@@ -1 +1 @@
-"9712:0850"
+"9712:0914"

source/common.h

@@ -375,6 +375,46 @@ auto is_separator_or(auto pred, char c)
 }
 
 
+auto peek(
+    std::string_view line,
+    int i,
+    int num
+    )
+{
+    return
+        (i + num < std::ssize(line) && i + num >= 0)
+        ? line[i + num]
+        : '\0';
+}
+
+
+//G encoding-prefix: one of
+//G     'u8' 'u' 'uR' 'u8R' 'U' 'UR' 'L' 'LR' 'R'
+//G
+auto is_encoding_prefix_and(std::string_view line, int i, char next) {
+    auto peek1 = peek(line, i, 1);
+    auto peek2 = peek(line, i, 2);
+    auto peek3 = peek(line, i, 3);
+    if (line[i] == next) { return 1; } // "
+    else if (line[i] == 'u') {
+        if (peek1 == next) { return 2; } // u"
+        else if (peek1 == '8' && peek2 == next) { return 3; } // u8"
+        else if (peek1 == 'R' && peek2 == next) { return 3; } // uR"
+        else if (peek1 == '8' && peek2 == 'R' && peek3 == next) { return 4; } // u8R"
+    }
+    else if (line[i] == 'U') {
+        if (peek1 == next) { return 2; } // U"
+        else if (peek1 == 'R' && peek2 == next) { return 3; } // UR"
+    }
+    else if (line[i] == 'L') {
+        if (peek1 == next) { return 2; } // L"
+        else if (peek1 == 'R' && peek2 == next) { return 3; } // LR"
+    }
+    else if (line[i] == 'R' && peek1 == next) { return 2; } // R"
+    return 0;
+};
+
+
 //  Bool to string
 //
 template<typename T>

source/io.h

@@ -741,6 +741,15 @@ auto process_cpp2_line(
             break;default: ;
             }
         }
+        else if (
+            auto j = is_encoding_prefix_and(line, i, '\'');
+            j > 1
+            )
+        {
+            in_char_literal = true;
+            i += j-1;
+            prev = line[i-1];
+        }
         else
         {
             switch (line[i])

source/lex.h

@@ -1236,29 +1236,6 @@ auto lex_line(
         auto peek2 = peek(2);
         auto peek3 = peek(3);
 
-        //G encoding-prefix: one of
-        //G     'u8' 'u' 'uR' 'u8R' 'U' 'UR' 'L' 'LR' 'R'
-        //G
-        auto is_encoding_prefix_and = [&](char next) {
-            if (line[i] == next)                                        { return 1; } // "
-            else if (line[i] == 'u') {
-                if (peek1 == next)                                      { return 2; } // u"
-                else if (peek1 == '8' && peek2 == next)                 { return 3; } // u8"
-                else if (peek1 == 'R' && peek2 == next)                 { return 3; } // uR"
-                else if (peek1 == '8' && peek2 == 'R' && peek3 == next) { return 4; } // u8R"
-            }
-            else if (line[i] == 'U') {
-                if ( peek1 == next)                                     { return 2; } // U"
-                else if (peek1 == 'R' && peek2 == next)                 { return 3; } // UR"
-            }
-            else if (line[i] == 'L') {
-                if ( peek1 == next )                                    { return 2; } // L"
-                else if (peek1 == 'R' && peek2 == next)                 { return 3; } // LR"
-            }
-            else if (line[i] == 'R' && peek1 == next)                   { return 2; } // R"
-            return 0;
-        };
-
         //  If we're currently in a multiline comment,
         //  the only thing to look for is the */ comment end
         //
@@ -1728,7 +1705,7 @@ auto lex_line(
                 //G interpolation:
                 //G     '(' expression ')' '$'
                 //G
-                else if (auto j = is_encoding_prefix_and('\"')) {
+                else if (auto j = is_encoding_prefix_and(line, i, '\"')) {
                     // if peek(j-2) is 'R' it means that we deal with raw-string literal
                     if (peek(j-2) == 'R') {
                         auto seq_pos = i + j;
@@ -1805,7 +1782,7 @@ auto lex_line(
                 //G     c-char
                 //G     c-char-seq c-char
                 //G
-                else if (auto j = is_encoding_prefix_and('\'')) {
+                else if (auto j = is_encoding_prefix_and(line, i, '\'')) {
                     auto len = peek_is_sc_char(j, '\'');
                     if (len > 0) {
                         j += len;