viml/parser/expressions: Add support for parsing assignments

4 files changed, 35 insertions, 14 deletions

diff --git a/test/symbolic/klee/viml_expressions_parser.c b/test/symbolic/klee/viml_expressions_parser.c
index 9448937430..fd75e8d355 100644
--- a/test/symbolic/klee/viml_expressions_parser.c
+++ b/test/symbolic/klee/viml_expressions_parser.c
@@ -48,7 +48,8 @@ int main(const int argc, const char *const *const argv,
   klee_make_symbolic(&shift, sizeof(shift), "shift");
   klee_make_symbolic(&flags, sizeof(flags), "flags");
   klee_assume(shift < INPUT_SIZE);
-  klee_assume(flags <= (kExprFlagsMulti|kExprFlagsDisallowEOC));
+  klee_assume(
+      flags <= (kExprFlagsMulti|kExprFlagsDisallowEOC|kExprFlagsParseLet));
 #endif
 
   ParserLine plines[] = {
diff --git a/test/unit/viml/expressions/lexer_spec.lua b/test/unit/viml/expressions/lexer_spec.lua
index 75a641c48a..1b57a24ad5 100644
--- a/test/unit/viml/expressions/lexer_spec.lua
+++ b/test/unit/viml/expressions/lexer_spec.lua
@@ -13,6 +13,7 @@ local conv_ccs = viml_helpers.conv_ccs
 local new_pstate = viml_helpers.new_pstate
 local conv_cmp_type = viml_helpers.conv_cmp_type
 local pstate_set_str = viml_helpers.pstate_set_str
+local conv_expr_asgn_type = viml_helpers.conv_expr_asgn_type
 
 local shallowcopy = global_helpers.shallowcopy
 local intchar2lua = global_helpers.intchar2lua
@@ -52,6 +53,8 @@ child_call_once(function()
     [tonumber(lib.kExprLexParenthesis)] = 'Parenthesis',
     [tonumber(lib.kExprLexComma)] = 'Comma',
     [tonumber(lib.kExprLexArrow)] = 'Arrow',
+
+    [tonumber(lib.kExprLexAssignment)] = 'Assignment',
   }
 
   eltkn_mul_type_tab = {
@@ -118,6 +121,8 @@ local function eltkn2lua(pstate, tkn)
     ret.data.val = tonumber(tkn.data.num.is_float
                             and tkn.data.num.val.floating
                             or tkn.data.num.val.integer)
+  elseif ret.type == 'Assignment' then
+    ret.data = { type = conv_expr_asgn_type(tkn.data.ass.type) }
   elseif ret.type == 'Invalid' then
     ret.data = { error = ffi.string(tkn.data.err.msg) }
   end
@@ -198,7 +203,9 @@ describe('Expressions lexer', function()
     singl_eltkn_test('Question', '?')
     singl_eltkn_test('Colon', ':')
     singl_eltkn_test('Dot', '.')
+    singl_eltkn_test('Assignment', '.=', {type='Concat'})
     singl_eltkn_test('Plus', '+')
+    singl_eltkn_test('Assignment', '+=', {type='Add'})
     singl_eltkn_test('Comma', ',')
     singl_eltkn_test('Multiplication', '*', {type='Mul'})
     singl_eltkn_test('Multiplication', '/', {type='Div'})
@@ -266,12 +273,13 @@ describe('Expressions lexer', function()
     singl_eltkn_test('DoubleQuotedString', '"x\\"', {closed=false})
     singl_eltkn_test('DoubleQuotedString', '"\\"x', {closed=false})
     singl_eltkn_test('Not', '!')
-    singl_eltkn_test('Invalid', '=', {error='E15: Expected == or =~: %.*s'})
+    singl_eltkn_test('Assignment', '=', {type='Plain'})
     comparison_test('==', '!=', 'Equal')
     comparison_test('=~', '!~', 'Matches')
     comparison_test('>', '<=', 'Greater')
     comparison_test('>=', '<', 'GreaterOrEqual')
     singl_eltkn_test('Minus', '-')
+    singl_eltkn_test('Assignment', '-=', {type='Subtract'})
     singl_eltkn_test('Arrow', '->')
     singl_eltkn_test('Invalid', '~', {error='E15: Unidentified character: %.*s'})
     simple_test({{data=nil, size=0}}, 'EOC', 0, {error='start.col >= #pstr'})
diff --git a/test/unit/viml/expressions/parser_spec.lua b/test/unit/viml/expressions/parser_spec.lua
index cfc9fe95ac..810d7bfbc6 100644
--- a/test/unit/viml/expressions/parser_spec.lua
+++ b/test/unit/viml/expressions/parser_spec.lua
@@ -18,6 +18,7 @@ local conv_ccs = viml_helpers.conv_ccs
 local new_pstate = viml_helpers.new_pstate
 local conv_cmp_type = viml_helpers.conv_cmp_type
 local pstate_set_str = viml_helpers.pstate_set_str
+local conv_expr_asgn_type = viml_helpers.conv_expr_asgn_type
 
 local mergedicts_copy = global_helpers.mergedicts_copy
 local format_string = global_helpers.format_string
@@ -109,6 +110,7 @@ make_enum_conv_tab(lib, {
   'kExprNodeMod',
   'kExprNodeOption',
   'kExprNodeEnvironment',
+  'kExprNodeAssignment',
 }, 'kExprNode', function(ret) east_node_type_tab = ret end)
 
 local function conv_east_node_type(typ)
@@ -174,6 +176,8 @@ local function eastnode2lua(pstate, eastnode, checked_nodes)
     typ = ('%s(ident=%s)'):format(
       typ,
       ffi.string(eastnode.data.env.ident, eastnode.data.env.ident_len))
+  elseif typ == 'Assignment' then
+    typ = ('%s(%s)'):format(typ, conv_expr_asgn_type(eastnode.data.ass.type))
   end
   ret_str = typ .. ':' .. ret_str
   local can_simplify = not ret.children
@@ -3976,27 +3980,20 @@ describe('Expressions parser', function()
       --           012345
       ast = {
         {
-          'Comparison(type=Equal,inv=0,ccs=UseOption):0:3:=',
+          'Assignment(Add):0:1: +=',
           children = {
-            {
-              'BinaryPlus:0:1: +',
-              children = {
-                'PlainIdentifier(scope=0,ident=a):0:0:a',
-                'Missing:0:3:',
-              },
-            },
+            'PlainIdentifier(scope=0,ident=a):0:0:a',
             'PlainIdentifier(scope=0,ident=b):0:4: b',
           },
         },
       },
       err = {
-        arg = '= b',
-        msg = 'E15: Expected == or =~: %.*s',
+        arg = '+= b',
+        msg = 'E15: Misplaced assignment: %.*s',
       },
     }, {
       hl('IdentifierName', 'a'),
-      hl('BinaryPlus', '+', 1),
-      hl('InvalidComparison', '='),
+      hl('InvalidAssignmentWithAddition', '+=', 1),
       hl('IdentifierName', 'b', 1),
     })
     check_parsing('a + b == c + d', {
@@ -7347,4 +7344,6 @@ describe('Expressions parser', function()
       },
     })
   end)
+  -- FIXME: Test assignments thoroughly
+  -- FIXME: Test that parsing assignments can be used for `:for` pre-`in` part.
 end)
diff --git a/test/unit/viml/helpers.lua b/test/unit/viml/helpers.lua
index 9d2d7b61c7..9d8102e023 100644
--- a/test/unit/viml/helpers.lua
+++ b/test/unit/viml/helpers.lua
@@ -107,6 +107,18 @@ local function conv_ccs(ccs)
   return conv_enum(ccs_tab, ccs)
 end
 
+local expr_asgn_type_tab
+make_enum_conv_tab(lib, {
+  'kExprAsgnPlain',
+  'kExprAsgnAdd',
+  'kExprAsgnSubtract',
+  'kExprAsgnConcat',
+}, 'kExprAsgn', function(ret) expr_asgn_type_tab = ret end)
+
+local function conv_expr_asgn_type(expr_asgn_type)
+  return conv_enum(expr_asgn_type_tab, expr_asgn_type)
+end
+
 return {
   conv_ccs = conv_ccs,
   pline2lua = pline2lua,
@@ -114,4 +126,5 @@ return {
   new_pstate = new_pstate,
   conv_cmp_type = conv_cmp_type,
   pstate_set_str = pstate_set_str,
+  conv_expr_asgn_type = conv_expr_asgn_type,
 }