Don't store the term sigil in the identifier name

spec/CHANGELOG.md

@@ -2,12 +2,18 @@
 
 ## Unreleased
 
-  - Support astral Unicode characters. (#179)
+  - Support astral Unicode characters. (#174)
 
     Unicode characters from outside of the Basic Multilingual Plane can now
     be used in values of `TextElements` and `StringLiterals`. This means all
     characters in the U+10000 to U+10FFFF range. 🎉
 
+  - Don't store the `-` sigil in `Identifiers` of `Terms`. (#142)
+
+    The `-` sigil is no longer part of the term's `Identifier`. This is now
+    consistent with how `Identifiers` of variables don't include the `$`
+    sigil either.
+
 ## 0.7.0 (October 15, 2018)
 
   - Relax the indentation requirement. (#87)

spec/fluent.ebnf

@@ -12,7 +12,7 @@ Entry               ::= (Message line_end)
                       | (Term line_end)
                       | CommentLine
 Message             ::= Identifier blank_inline? "=" blank_inline? ((Pattern Attribute*) | (Attribute+))
-Term                ::= TermIdentifier blank_inline? "=" blank_inline? Value Attribute*
+Term                ::= "-" Identifier blank_inline? "=" blank_inline? Value Attribute*
 
 /* Adjacent comment lines of the same comment type are joined together during
  * the AST construction. */
@@ -62,8 +62,8 @@ NumberLiteral       ::= "-"? digit+ ("." digit+)?
 
 /* Inline Expressions */
 MessageReference    ::= Identifier
-TermReference       ::= TermIdentifier
-VariableReference   ::= VariableIdentifier
+TermReference       ::= "-" Identifier
+VariableReference   ::= "$" Identifier
 CallExpression      ::= Function blank? "(" blank? argument_list blank? ")"
 argument_list       ::= (Argument blank? "," blank?)* Argument?
 Argument            ::= NamedArgument
@@ -80,11 +80,8 @@ DefaultVariant      ::= line_end blank? "*" VariantKey blank_inline? Value
 VariantKey          ::= "[" blank? (NumberLiteral | Identifier) blank? "]"
 
 /* Identifiers */
-Identifier          ::= identifier
-TermIdentifier      ::= "-" identifier
-VariableIdentifier  ::= "$" identifier
+Identifier          ::= [a-zA-Z] [a-zA-Z0-9_-]*
 Function            ::= [A-Z] [A-Z_?-]*
-identifier          ::= [a-zA-Z] [a-zA-Z0-9_-]*
 
 /* Characters */
 backslash           ::= "\\"

syntax/grammar.mjs

@@ -56,7 +56,8 @@ let Message = defer(() =>
 
 let Term = defer(() =>
     sequence(
-        TermIdentifier.abstract,
+        string("-"),
+        Identifier.abstract,
         maybe(blank_inline),
         string("="),
         maybe(blank_inline),
@@ -223,10 +224,18 @@ let MessageReference = defer(() =>
     Identifier.chain(into(FTL.MessageReference)));
 
 let TermReference = defer(() =>
-    TermIdentifier.chain(into(FTL.TermReference)));
+    sequence(
+        string("-"),
+        Identifier)
+    .map(element_at(1))
+    .chain(into(FTL.TermReference)));
 
 let VariableReference = defer(() =>
-    VariableIdentifier.chain(into(FTL.VariableReference)));
+    sequence(
+        string("$"),
+        Identifier)
+    .map(element_at(1))
+    .chain(into(FTL.VariableReference)));
 
 let CallExpression = defer(() =>
     sequence(
@@ -343,22 +352,14 @@ let VariantKey = defer(() =>
 /* ----------- */
 /* Identifiers */
 
-let Identifier = defer(() =>
-    identifier.chain(into(FTL.Identifier)));
-
-let TermIdentifier = defer(() =>
+let Identifier =
     sequence(
-        string("-"),
-        identifier)
+        charset("a-zA-Z"),
+        repeat(
+            charset("a-zA-Z0-9_-")))
+    .map(flatten(1))
     .map(join)
-    .chain(into(FTL.Identifier)));
-
-let VariableIdentifier = defer(() =>
-    sequence(
-        string("$"),
-        identifier)
-    .map(element_at(1))
-    .chain(into(FTL.Identifier)));
+    .chain(into(FTL.Identifier));
 
 let Function =
     sequence(
@@ -369,14 +370,6 @@ let Function =
     .map(join)
     .chain(into(FTL.Function));
 
-let identifier =
-    sequence(
-        charset("a-zA-Z"),
-        repeat(
-            charset("a-zA-Z0-9_-")))
-    .map(flatten(1))
-    .map(join);
-
 /* ---------- */
 /* Characters */
 

test/fixtures/call_expressions.json

@@ -548,7 +548,7 @@
                                     "type": "TermReference",
                                     "id": {
                                         "type": "Identifier",
-                                        "name": "-msg"
+                                        "name": "msg"
                                     }
                                 }
                             ],

test/fixtures/comments.json

@@ -30,7 +30,7 @@
             "type": "Term",
             "id": {
                 "type": "Identifier",
-                "name": "-term"
+                "name": "term"
             },
             "value": {
                 "type": "Pattern",

test/fixtures/member_expressions.json

@@ -18,7 +18,7 @@
                                 "type": "TermReference",
                                 "id": {
                                     "type": "Identifier",
-                                    "name": "-term"
+                                    "name": "term"
                                 }
                             },
                             "key": {

test/fixtures/mixed_entries.json

@@ -13,7 +13,7 @@
             "type": "Term",
             "id": {
                 "type": "Identifier",
-                "name": "-brand-name"
+                "name": "brand-name"
             },
             "value": {
                 "type": "Pattern",

test/fixtures/reference_expressions.json

@@ -40,7 +40,7 @@
                             "type": "TermReference",
                             "id": {
                                 "type": "Identifier",
-                                "name": "-term"
+                                "name": "term"
                             }
                         }
                     }

test/fixtures/select_expressions.json

@@ -92,7 +92,7 @@
                                     "type": "TermReference",
                                     "id": {
                                         "type": "Identifier",
-                                        "name": "-term"
+                                        "name": "term"
                                     }
                                 },
                                 "name": {

test/fixtures/terms.json

@@ -5,7 +5,7 @@
             "type": "Term",
             "id": {
                 "type": "Identifier",
-                "name": "-term01"
+                "name": "term01"
             },
             "value": {
                 "type": "Pattern",
@@ -40,7 +40,7 @@
             "type": "Term",
             "id": {
                 "type": "Identifier",
-                "name": "-term02"
+                "name": "term02"
             },
             "value": {
                 "type": "Pattern",

test/fixtures/variables.ftl

@@ -0,0 +1,17 @@
+key01 = {$var}
+key02 = {   $var   }
+key03 = {
+    $var
+}
+key04 = {
+$var}
+
+
+## Errors
+
+# ERROR Missing variable identifier
+err01 = {$}
+# ERROR Double $$
+err02 = {$$var}
+# ERROR Invalid first char of the identifier
+err03 = {$-var}

test/fixtures/variables.json

@@ -0,0 +1,132 @@
+{
+    "type": "Resource",
+    "body": [
+        {
+            "type": "Message",
+            "id": {
+                "type": "Identifier",
+                "name": "key01"
+            },
+            "value": {
+                "type": "Pattern",
+                "elements": [
+                    {
+                        "type": "Placeable",
+                        "expression": {
+                            "type": "VariableReference",
+                            "id": {
+                                "type": "Identifier",
+                                "name": "var"
+                            }
+                        }
+                    }
+                ]
+            },
+            "attributes": [],
+            "comment": null
+        },
+        {
+            "type": "Message",
+            "id": {
+                "type": "Identifier",
+                "name": "key02"
+            },
+            "value": {
+                "type": "Pattern",
+                "elements": [
+                    {
+                        "type": "Placeable",
+                        "expression": {
+                            "type": "VariableReference",
+                            "id": {
+                                "type": "Identifier",
+                                "name": "var"
+                            }
+                        }
+                    }
+                ]
+            },
+            "attributes": [],
+            "comment": null
+        },
+        {
+            "type": "Message",
+            "id": {
+                "type": "Identifier",
+                "name": "key03"
+            },
+            "value": {
+                "type": "Pattern",
+                "elements": [
+                    {
+                        "type": "Placeable",
+                        "expression": {
+                            "type": "VariableReference",
+                            "id": {
+                                "type": "Identifier",
+                                "name": "var"
+                            }
+                        }
+                    }
+                ]
+            },
+            "attributes": [],
+            "comment": null
+        },
+        {
+            "type": "Message",
+            "id": {
+                "type": "Identifier",
+                "name": "key04"
+            },
+            "value": {
+                "type": "Pattern",
+                "elements": [
+                    {
+                        "type": "Placeable",
+                        "expression": {
+                            "type": "VariableReference",
+                            "id": {
+                                "type": "Identifier",
+                                "name": "var"
+                            }
+                        }
+                    }
+                ]
+            },
+            "attributes": [],
+            "comment": null
+        },
+        {
+            "type": "GroupComment",
+            "content": "Errors"
+        },
+        {
+            "type": "Comment",
+            "content": "ERROR Missing variable identifier"
+        },
+        {
+            "type": "Junk",
+            "annotations": [],
+            "content": "err01 = {$}\n"
+        },
+        {
+            "type": "Comment",
+            "content": "ERROR Double $$"
+        },
+        {
+            "type": "Junk",
+            "annotations": [],
+            "content": "err02 = {$$var}\n"
+        },
+        {
+            "type": "Comment",
+            "content": "ERROR Invalid first char of the identifier"
+        },
+        {
+            "type": "Junk",
+            "annotations": [],
+            "content": "err03 = {$-var}\n"
+        }
+    ]
+}

test/fixtures/variant_keys.json

@@ -5,7 +5,7 @@
             "type": "Term",
             "id": {
                 "type": "Identifier",
-                "name": "-simple-identifier"
+                "name": "simple-identifier"
             },
             "value": {
                 "type": "VariantList",
@@ -36,7 +36,7 @@
             "type": "Term",
             "id": {
                 "type": "Identifier",
-                "name": "-identifier-surrounded-by-whitespace"
+                "name": "identifier-surrounded-by-whitespace"
             },
             "value": {
                 "type": "VariantList",
@@ -67,7 +67,7 @@
             "type": "Term",
             "id": {
                 "type": "Identifier",
-                "name": "-int-number"
+                "name": "int-number"
             },
             "value": {
                 "type": "VariantList",
@@ -98,7 +98,7 @@
             "type": "Term",
             "id": {
                 "type": "Identifier",
-                "name": "-float-number"
+                "name": "float-number"
             },
             "value": {
                 "type": "VariantList",