Constantize string error messages (#50)

src/ameba/rule/comparison_to_boolean.cr

@@ -26,6 +26,8 @@ module Ameba::Rule
       description = "Disallows comparison to booleans"
     end
 
+    MSG = "Comparison to a boolean is pointless"
+
     def test(source)
       AST::Visitor.new self, source
     end
@@ -37,7 +39,7 @@ module Ameba::Rule
 
       return unless comparison? && to_boolean?
 
-      source.error self, node.location, "Comparison to a boolean is pointless"
+      source.error self, node.location, MSG
     end
   end
 end

src/ameba/rule/constant_names.cr

@@ -27,6 +27,8 @@ module Ameba::Rule
       description = "Enforces constant names to be in screaming case"
     end
 
+    MSG = "Constant name should be screaming-cased: %s, not %s"
+
     def test(source)
       AST::Visitor.new self, source
     end
@@ -36,8 +38,7 @@ module Ameba::Rule
         name = target.names.first
         return if (expected = name.upcase) == name
 
-        source.error self, node.location,
-          "Constant name should be screaming-cased: #{expected}, not #{name}"
+        source.error self, node.location, sprintf(MSG, expected, name)
       end
     end
   end

src/ameba/rule/debugger_statement.cr

@@ -16,6 +16,8 @@ module Ameba::Rule
       description = "Disallows calls to debugger"
     end
 
+    MSG = "Possible forgotten debugger statement detected"
+
     def test(source)
       AST::Visitor.new self, source
     end
@@ -25,8 +27,7 @@ module Ameba::Rule
                     node.args.empty? &&
                     node.obj.nil?
 
-      source.error self, node.location,
-        "Possible forgotten debugger statement detected"
+      source.error self, node.location, MSG
     end
   end
 end

src/ameba/rule/empty_ensure.cr

@@ -37,6 +37,8 @@ module Ameba::Rule
       description = "Disallows empty ensure statement"
     end
 
+    MSG = "Empty `ensure` block detected"
+
     def test(source)
       AST::Visitor.new self, source
     end
@@ -45,7 +47,7 @@ module Ameba::Rule
       node_ensure = node.ensure
       return if node_ensure.nil? || !node_ensure.nop?
 
-      source.error self, node.location, "Empty `ensure` block detected"
+      source.error self, node.location, MSG
     end
   end
 end

src/ameba/rule/empty_expression.cr

@@ -35,6 +35,9 @@ module Ameba::Rule
       description = "Disallows empty expressions"
     end
 
+    MSG      = "Avoid empty expression %s"
+    MSG_EXRS = "Avoid empty expressions"
+
     def test(source)
       AST::Visitor.new self, source
     end
@@ -44,12 +47,12 @@ module Ameba::Rule
 
       return if exp.nil? || exp == "nil"
 
-      source.error self, node.location, "Avoid empty expression '#{exp}'"
+      source.error self, node.location, MSG % exp
     end
 
     def test(source, node : Crystal::Expressions)
       if node.expressions.size == 1 && node.expressions.first.nop?
-        source.error self, node.location, "Avoid empty expressions"
+        source.error self, node.location, MSG_EXRS
       end
     end
   end

src/ameba/rule/hash_duplicated_key.cr

@@ -25,6 +25,8 @@ module Ameba::Rule
       description = "Disallows duplicated keys in hash literals"
     end
 
+    MSG = "Duplicated keys in hash literal: %s"
+
     def test(source)
       AST::Visitor.new self, source
     end
@@ -32,8 +34,7 @@ module Ameba::Rule
     def test(source, node : Crystal::HashLiteral)
       return unless (keys = duplicated_keys(node.entries)).any?
 
-      source.error self, node.location,
-        "Duplicated keys in hash literal: #{keys.join(", ")}"
+      source.error self, node.location, MSG % keys.join(", ")
     end
 
     private def duplicated_keys(entries)

src/ameba/rule/large_numbers.cr

@@ -33,6 +33,8 @@ module Ameba::Rule
       int_min_digits = 5
     end
 
+    MSG = "Large numbers should be written with underscores: %s"
+
     def test(source)
       Tokenizer.new(source).run do |token|
         next unless token.type == :NUMBER && decimal?(token.raw)
@@ -40,8 +42,7 @@ module Ameba::Rule
         parsed = parse_number token.raw
 
         if allowed?(*parsed) && (expected = underscored *parsed) != token.raw
-          source.error self, token.location,
-            "Large numbers should be written with underscores: #{expected}"
+          source.error self, token.location, MSG % expected
         end
       end
     end

src/ameba/rule/line_length.cr

@@ -16,11 +16,13 @@ module Ameba::Rule
       max_length = 80
     end
 
+    MSG = "Line too long"
+
     def test(source)
       source.lines.each_with_index do |line, index|
         next unless line.size > max_length
 
-        source.error self, index + 1, line.size, "Line too long"
+        source.error self, index + 1, line.size, MSG
       end
     end
   end

src/ameba/rule/literal_in_condition.cr

@@ -28,13 +28,15 @@ module Ameba::Rule
         a literal in place of a variable or predicate function"
     end
 
+    MSG = "Literal value found in conditional"
+
     def test(source)
       AST::Visitor.new self, source
     end
 
     def check_node(source, node)
       return unless literal?(node.cond)
-      source.error self, node.location, "Literal value found in conditional"
+      source.error self, node.location, MSG
     end
 
     def test(source, node : Crystal::If)

src/ameba/rule/literal_in_interpolation.cr

@@ -23,6 +23,8 @@ module Ameba::Rule
       description = "Disallows useless string interpolations"
     end
 
+    MSG = "Literal value found in interpolation"
+
     def test(source)
       AST::Visitor.new self, source
     end
@@ -30,7 +32,7 @@ module Ameba::Rule
     def test(source, node : Crystal::StringInterpolation)
       found = node.expressions.any? { |e| !string_literal?(e) && literal?(e) }
       return unless found
-      source.error self, node.location, "Literal value found in interpolation"
+      source.error self, node.location, MSG
     end
   end
 end

src/ameba/rule/method_names.cr

@@ -43,6 +43,8 @@ module Ameba::Rule
       description = "Enforces method names to be in underscored case"
     end
 
+    MSG = "Method name should be underscore-cased: %s, not %s"
+
     def test(source)
       AST::Visitor.new self, source
     end
@@ -50,8 +52,7 @@ module Ameba::Rule
     def test(source, node : Crystal::Def)
       return if (expected = node.name.underscore) == node.name
 
-      source.error self, node.location,
-        "Method name should be underscore-cased: #{expected}, not #{node.name}"
+      source.error self, node.location, sprintf(MSG, expected, node.name)
     end
   end
 end

src/ameba/rule/negated_conditions_in_unless.cr

@@ -32,14 +32,15 @@ module Ameba::Rule
       description = "Disallows negated conditions in unless"
     end
 
+    MSG = "Avoid negated conditions in unless blocks"
+
     def test(source)
       AST::Visitor.new self, source
     end
 
     def test(source, node : Crystal::Unless)
       return unless negated_condition? node.cond
-      source.error self, node.location,
-        "Avoid negated conditions in unless blocks"
+      source.error self, node.location, MSG
     end
 
     private def negated_condition?(node)

src/ameba/rule/percent_arrays.cr

@@ -31,6 +31,8 @@ module Ameba::Rule
       symbol_array_unwanted_symbols = ",:"
     end
 
+    MSG = "Symbols `%s` may be unwanted in %s array literals"
+
     def test(source)
       error = start_token = nil
 
@@ -62,7 +64,7 @@ module Ameba::Rule
 
     private def check_array_entry(entry, symbols, literal)
       return unless entry =~ /[#{symbols}]/
-      "Symbols `#{symbols}` may be unwanted in #{literal} array literals"
+      sprintf(MSG, symbols, literal)
     end
   end
 end

src/ameba/rule/predicate_name.cr

@@ -34,6 +34,8 @@ module Ameba::Rule
       description = "Disallows tautological predicate names"
     end
 
+    MSG = "Favour method name '%s?' over '%s'"
+
     def test(source)
       AST::Visitor.new self, source
     end
@@ -43,8 +45,7 @@ module Ameba::Rule
         alternative = $2
         return unless alternative =~ /^[a-z][a-zA-Z_0-9]*$/
 
-        source.error self, node.location,
-          "Favour method name '#{alternative}?' over '#{node.name}'"
+        source.error self, node.location, sprintf(MSG, alternative, node.name)
       end
     end
   end

src/ameba/rule/rand_zero.cr

@@ -28,6 +28,8 @@ module Ameba::Rule
       description = "Disallows rand zero calls"
     end
 
+    MSG = "%s always returns 0"
+
     def test(source)
       AST::Visitor.new self, source
     end
@@ -40,7 +42,7 @@ module Ameba::Rule
                     (value = arg.value) &&
                     (value == "0" || value == "1")
 
-      source.error self, node.location, "#{node} always returns 0"
+      source.error self, node.location, MSG % node
     end
   end
 end

src/ameba/rule/redundant_begin.cr

@@ -62,6 +62,8 @@ module Ameba::Rule
       description = "Disallows redundant begin blocks"
     end
 
+    MSG = "Redundant `begin` block detected"
+
     def test(source)
       AST::Visitor.new self, source
     end
@@ -69,7 +71,7 @@ module Ameba::Rule
     def test(source, node : Crystal::Def)
       return unless redundant_begin?(source, node)
 
-      source.error self, node.location, "Redundant `begin` block detected"
+      source.error self, node.location, MSG
     end
 
     private def redundant_begin?(source, node)

src/ameba/rule/shadowed_exception.cr

@@ -39,6 +39,8 @@ module Ameba::Rule
       description = "Disallows rescued exception that get shadowed"
     end
 
+    MSG = "Exception handler has shadowed exceptions: %s"
+
     def test(source)
       AST::Visitor.new self, source
     end
@@ -47,8 +49,7 @@ module Ameba::Rule
       return unless excs = node.rescues
 
       if (excs = shadowed excs.map(&.types)).any?
-        source.error self, node.location,
-          "Exception handler has shadowed exceptions: #{excs.join(", ")}"
+        source.error self, node.location, MSG % excs.join(", ")
       end
     end
 

src/ameba/rule/trailing_blank_lines.cr

@@ -13,10 +13,11 @@ module Ameba::Rule
       description = "Disallows trailing blank lines"
     end
 
+    MSG = "Blank lines detected at the end of the file"
+
     def test(source)
       if source.lines.size > 1 && source.lines[-2, 2].join.strip.empty?
-        source.error self, source.lines.size, 1,
-          "Blank lines detected at the end of the file"
+        source.error self, source.lines.size, 1, MSG
       end
     end
   end

src/ameba/rule/trailing_whitespace.cr

@@ -13,10 +13,12 @@ module Ameba::Rule
       description = "Disallows trailing whitespaces"
     end
 
+    MSG = "Trailing whitespace detected"
+
     def test(source)
       source.lines.each_with_index do |line, index|
         next unless line =~ /\s$/
-        source.error self, index + 1, line.size, "Trailing whitespace detected"
+        source.error self, index + 1, line.size, MSG
       end
     end
   end

src/ameba/rule/type_names.cr

@@ -57,6 +57,8 @@ module Ameba::Rule
       description = "Enforces type names in camelcase manner"
     end
 
+    MSG = "Type name should be camelcased: %s, but it was %s"
+
     def test(source)
       AST::Visitor.new self, source
     end
@@ -66,8 +68,7 @@ module Ameba::Rule
       expected = name.camelcase
       return if expected == name
 
-      source.error self, node.location,
-        "Type name should be camelcased: #{expected}, but it was #{name}"
+      source.error self, node.location, sprintf(MSG, expected, name)
     end
 
     def test(source, node : Crystal::ClassDef)

src/ameba/rule/unless_else.cr

@@ -48,13 +48,15 @@ module Ameba::Rule
       description = "Disallows the use of an `else` block with the `unless`"
     end
 
+    MSG = "Favour if over unless with else"
+
     def test(source)
       AST::Visitor.new self, source
     end
 
     def test(source, node : Crystal::Unless)
       return if node.else.nop?
-      source.error self, node.location, "Favour if over unless with else"
+      source.error self, node.location, MSG
     end
   end
 end

src/ameba/rule/unneeded_disable_directive.cr

@@ -23,6 +23,8 @@ module Ameba::Rule
       description = "Reports unneeded disable directives in comments"
     end
 
+    MSG = "Unnecessary disabling of %s"
+
     def test(source)
       Tokenizer.new(source).run do |token|
         next unless token.type == :COMMENT
@@ -30,8 +32,7 @@ module Ameba::Rule
         next unless names = unneeded_disables(source, directive, token.location)
         next unless names.any?
 
-        source.error self, token.location,
-          "Unnecessary disabling of #{names.join(", ")}"
+        source.error self, token.location, MSG % names.join(", ")
       end
     end
 

src/ameba/rule/useless_condition_in_when.cr

@@ -36,6 +36,8 @@ module Ameba::Rule
       description = "Disallows useless conditions in when"
     end
 
+    MSG = "Useless condition in when detected"
+
     # TODO: condition.cond may be a complex ASTNode with
     # useless inner conditions. We might need to improve this
     # simple implementation in future.
@@ -46,7 +48,7 @@ module Ameba::Rule
                   .map(&.to_s)
                   .none? { |c| c == cond_s }
 
-      source.error self, cond.location, "Useless condition in when detected"
+      source.error self, cond.location, MSG
     end
 
     def test(source)

src/ameba/rule/variable_names.cr

@@ -36,6 +36,8 @@ module Ameba::Rule
       description = "Enforces variable names to be in underscored case"
     end
 
+    MSG = "Var name should be underscore-cased: %s, not %s"
+
     def test(source)
       AST::Visitor.new self, source
     end
@@ -43,8 +45,7 @@ module Ameba::Rule
     private def check_node(source, node)
       return if (expected = node.name.underscore) == node.name
 
-      source.error self, node.location,
-        "Var name should be underscore-cased: #{expected}, not #{node.name}"
+      source.error self, node.location, sprintf(MSG, expected, node.name)
     end
 
     def test(source, node : Crystal::Var)

src/ameba/rule/while_true.cr

@@ -31,13 +31,15 @@ module Ameba::Rule
       description = "Disallows while statements with a true literal as condition"
     end
 
+    MSG = "While statement using true literal as condition"
+
     def test(source)
       AST::Visitor.new self, source
     end
 
     def test(source, node : Crystal::While)
       return unless node.cond.true_literal?
-      source.error self, node.location, "While statement using true literal as condition"
+      source.error self, node.location, MSG
     end
   end
 end