Type-checking macros via the Macro' type from the standard library.

20 files changed, 415 insertions, 165 deletions

diff --git a/stdlib/source/lux/data/number/frac.lux b/stdlib/source/lux/data/number/frac.lux
index 47ad25f30..633872f9c 100644
--- a/stdlib/source/lux/data/number/frac.lux
+++ b/stdlib/source/lux/data/number/frac.lux
@@ -5,6 +5,7 @@
     [monoid (#+ Monoid)]
     [equivalence (#+ Equivalence)]
     [codec (#+ Codec)]
+    [predicate (#+ Predicate)]
     ["." order (#+ Order)]]
    [control
     ["." try (#+ Try)]]
@@ -29,7 +30,7 @@
   ("lux f64 <" reference sample))
 
 (def: #export (<= reference sample)
-  {#.doc "Frac(tion) less-than-equal."}
+  {#.doc "Frac(tion) less-than or equal."}
   (-> Frac Frac Bit)
   (or ("lux f64 <" reference sample)
       ("lux f64 =" reference sample)))
@@ -40,11 +41,21 @@
   ("lux f64 <" sample reference))
 
 (def: #export (>= reference sample)
-  {#.doc "Frac(tion) greater-than-equal."}
+  {#.doc "Frac(tion) greater-than or equal."}
   (-> Frac Frac Bit)
   (or ("lux f64 <" sample reference)
       ("lux f64 =" sample reference)))
 
+(template [<comparison> <name>]
+  [(def: #export <name>
+     (Predicate Frac)
+     (<comparison> +0.0))]
+
+  [..> positive?]
+  [..< negative?]
+  [..= zero?]
+  )
+
 (template [<name> <op> <doc>]
   [(def: #export (<name> param subject)
      {#.doc <doc>}
@@ -63,7 +74,9 @@
   [(../ param subject)
    (..% param subject)])
 
-(def: #export negate (-> Frac Frac) (..* -1.0))
+(def: #export negate
+  (-> Frac Frac)
+  (..* -1.0))
 
 (def: #export (abs x)
   (-> Frac Frac)
diff --git a/stdlib/source/lux/data/number/int.lux b/stdlib/source/lux/data/number/int.lux
index fb1ceb224..f2bcdfeb9 100644
--- a/stdlib/source/lux/data/number/int.lux
+++ b/stdlib/source/lux/data/number/int.lux
@@ -7,6 +7,7 @@
     [monoid (#+ Monoid)]
     [equivalence (#+ Equivalence)]
     [codec (#+ Codec)]
+    [predicate (#+ Predicate)]
     ["." order (#+ Order)]]
    [control
     ["." try (#+ Try)]]
@@ -28,7 +29,7 @@
   ("lux i64 <" reference sample))
 
 (def: #export (<= reference sample)
-  {#.doc "Int(eger) less-than-equal."}
+  {#.doc "Int(eger) less-than or equal."}
   (-> Int Int Bit)
   (if ("lux i64 <" reference sample)
     #1
@@ -40,12 +41,22 @@
   ("lux i64 <" sample reference))
 
 (def: #export (>= reference sample)
-  {#.doc "Int(eger) greater-than-equal."}
+  {#.doc "Int(eger) greater-than or equal."}
   (-> Int Int Bit)
   (if ("lux i64 <" sample reference)
     #1
     ("lux i64 =" reference sample)))
 
+(template [<comparison> <name>]
+  [(def: #export <name>
+     (Predicate Int)
+     (<comparison> +0))]
+
+  [..> positive?]
+  [..< negative?]
+  [..= zero?]
+  )
+
 (template [<name> <test> <doc>]
   [(def: #export (<name> left right)
      {#.doc <doc>}
diff --git a/stdlib/source/lux/data/number/nat.lux b/stdlib/source/lux/data/number/nat.lux
index 9f370fb51..dd5e52ad1 100644
--- a/stdlib/source/lux/data/number/nat.lux
+++ b/stdlib/source/lux/data/number/nat.lux
@@ -48,7 +48,7 @@
         #0))))
 
 (def: #export (<= reference sample)
-  {#.doc "Nat(ural) less-than-equal."}
+  {#.doc "Nat(ural) less-than or equal."}
   (-> Nat Nat Bit)
   (if (..< reference sample)
     #1
@@ -60,7 +60,7 @@
   (..< sample reference))
 
 (def: #export (>= reference sample)
-  {#.doc "Nat(ural) greater-than-equal."}
+  {#.doc "Nat(ural) greater-than or equal."}
   (-> Nat Nat Bit)
   (if (..< sample reference)
     #1
diff --git a/stdlib/source/lux/data/number/rev.lux b/stdlib/source/lux/data/number/rev.lux
index 881043013..be4959726 100644
--- a/stdlib/source/lux/data/number/rev.lux
+++ b/stdlib/source/lux/data/number/rev.lux
@@ -32,7 +32,7 @@
            (:coerce Nat sample)))
 
 (def: #export (<= reference sample)
-  {#.doc "Rev(olution) less-than-equal."}
+  {#.doc "Rev(olution) less-than or equal."}
   (-> Rev Rev Bit)
   (if (//nat.< (:coerce Nat reference)
                (:coerce Nat sample))
@@ -45,7 +45,7 @@
   (..< sample reference))
 
 (def: #export (>= reference sample)
-  {#.doc "Rev(olution) greater-than-equal."}
+  {#.doc "Rev(olution) greater-than or equal."}
   (-> Rev Rev Bit)
   (if (..< sample reference)
     #1
diff --git a/stdlib/source/lux/data/text.lux b/stdlib/source/lux/data/text.lux
index fb2bc0728..c82dd5e41 100644
--- a/stdlib/source/lux/data/text.lux
+++ b/stdlib/source/lux/data/text.lux
@@ -106,6 +106,11 @@
     _
     false))
 
+(def: #export (encloses? boundary value)
+  (-> Text Text Bit)
+  (and (starts-with? boundary value)
+       (ends-with? boundary value)))
+
 (def: #export (contains? sub text)
   (-> Text Text Bit)
   (case ("lux text index" 0 sub text)
@@ -155,18 +160,18 @@
     #.None
     (#.Cons sample #.Nil)))
 
-(def: #export (replace-once pattern value template)
+(def: #export (replace-once pattern replacement template)
   (-> Text Text Text Text)
   (<| (maybe.default template)
       (do maybe.monad
         [[pre post] (split-with pattern template)]
-        (wrap ($_ "lux text concat" pre value post)))))
+        (wrap ($_ "lux text concat" pre replacement post)))))
 
-(def: #export (replace-all pattern value template)
+(def: #export (replace-all pattern replacement template)
   (-> Text Text Text Text)
   (case (..split-with pattern template)
     (#.Some [pre post])
-    ($_ "lux text concat" pre value (replace-all pattern value post))
+    ($_ "lux text concat" pre replacement (replace-all pattern replacement post))
 
     #.None
     template))
@@ -264,6 +269,7 @@
   (..enclose' ..double-quote))
 
 (def: #export space
+  Text
   " ")
 
 (def: #export (space? char)
diff --git a/stdlib/source/lux/tool/compiler/language/lux/phase/extension/analysis/lux.lux b/stdlib/source/lux/tool/compiler/language/lux/phase/extension/analysis/lux.lux
index 72096032a..59241f43d 100644
--- a/stdlib/source/lux/tool/compiler/language/lux/phase/extension/analysis/lux.lux
+++ b/stdlib/source/lux/tool/compiler/language/lux/phase/extension/analysis/lux.lux
@@ -192,16 +192,32 @@
 
 (def: (caster input output)
   (-> Type Type Handler)
-  (function (_ extension-name analyse archive args)
-    (case args
-      (^ (list valueC))
-      (do ////.monad
+  (..custom
+   [<c>.any
+    (function (_ extension-name phase archive valueC)
+      (do {@ ////.monad}
         [_ (typeA.infer output)]
         (typeA.with-type input
-          (analyse archive valueC)))
-      
-      _
-      (////analysis.throw ///.incorrect-arity [extension-name 1 (list.size args)]))))
+          (phase archive valueC))))]))
+
+(def: lux::macro
+  Handler
+  (..custom
+   [<c>.any
+    (function (_ extension-name phase archive valueC)
+      (do {@ ////.monad}
+        [_ (typeA.infer .Macro)
+         input-type (loop [input-name (name-of .Macro')]
+                      (do @
+                        [input-type (///.lift (meta.find-def (name-of .Macro')))]
+                        (case input-type
+                          (#.Definition [exported? def-type def-data def-value])
+                          (wrap (:coerce Type def-value))
+
+                          (#.Alias real-name)
+                          (recur real-name))))]
+        (typeA.with-type input-type
+          (phase archive valueC))))]))
 
 (def: (bundle::lux eval)
   (-> Eval Bundle)
@@ -211,7 +227,7 @@
       (///bundle.install "try" lux::try)
       (///bundle.install "check" (lux::check eval))
       (///bundle.install "coerce" (lux::coerce eval))
-      (///bundle.install "macro" (..caster .Macro' .Macro))
+      (///bundle.install "macro" ..lux::macro)
       (///bundle.install "check type" (..caster .Type .Type))
       (///bundle.install "in-module" lux::in-module)))
 
diff --git a/stdlib/source/program/aedifex.lux b/stdlib/source/program/aedifex.lux
index e29af6e7a..c2fa69e11 100644
--- a/stdlib/source/program/aedifex.lux
+++ b/stdlib/source/program/aedifex.lux
@@ -132,7 +132,7 @@
     (case (do try.monad
             [data data
              project (..project data)]
-            (/project.profile project profile))
+            (/project.profile profile project))
       (#try.Success profile)
       (case operation
         #/cli.POM
diff --git a/stdlib/source/program/aedifex/artifact/type.lux b/stdlib/source/program/aedifex/artifact/type.lux
new file mode 100644
index 000000000..e5836d13f
--- /dev/null
+++ b/stdlib/source/program/aedifex/artifact/type.lux
@@ -0,0 +1,16 @@
+(.module:
+  [lux (#- Type)])
+
+## https://maven.apache.org/ref/3.6.3/maven-core/artifact-handlers.html
+(type: #export Type
+  Text)
+
+(template [<type> <name>]
+  [(def: #export <name>
+     Type
+     <type>)]
+
+  ["tar" lux-library]
+  ["jar" jvm-library]
+  ["pom" pom]
+  )
diff --git a/stdlib/source/program/aedifex/command/build.lux b/stdlib/source/program/aedifex/command/build.lux
index eb7842e45..2c4b26aed 100644
--- a/stdlib/source/program/aedifex/command/build.lux
+++ b/stdlib/source/program/aedifex/command/build.lux
@@ -25,9 +25,10 @@
    ["#." action]
    ["#." command (#+ Command)]
    ["#." local]
-   ["#." artifact (#+ Group Name Artifact)]
    ["#." dependency (#+ Dependency Resolution)]
-   ["#." shell]])
+   ["#." shell]
+   ["#." artifact (#+ Group Name Artifact)
+    ["#/." type]]])
 
 (type: Finder
   (-> Resolution (Maybe Dependency)))
@@ -86,7 +87,7 @@
 (def: libraries
   (-> Resolution (List Path))
   (|>> dictionary.keys
-       (list.filter (|>> (get@ #///dependency.type) (text@= ///dependency.lux-library)))
+       (list.filter (|>> (get@ #///dependency.type) (text@= ///artifact/type.lux-library)))
        (list@map (|>> (get@ #///dependency.artifact) (///local.path file.system)))))
 
 (import: java/lang/String)
diff --git a/stdlib/source/program/aedifex/command/deploy.lux b/stdlib/source/program/aedifex/command/deploy.lux
index 1081322b4..a4b076733 100644
--- a/stdlib/source/program/aedifex/command/deploy.lux
+++ b/stdlib/source/program/aedifex/command/deploy.lux
@@ -30,7 +30,9 @@
    ["#." command (#+ Command)]
    ["#." dependency]
    ["#." pom]
-   ["#." hash]])
+   ["#." hash]
+   ["#." artifact
+    ["#/." type]]])
 
 (exception: #export (cannot-find-repository {repository Text}
                                             {options (Dictionary Text ///dependency.Repository)})
@@ -51,7 +53,7 @@
     (promise@wrap (exception.throw ..cannot-find-repository [repository (get@ #/.deploy-repositories profile)]))
 
     [(#.Some identity) (#.Some repository)]
-    (let [deploy! (: (-> ///dependency.Type Binary (Action Any))
+    (let [deploy! (: (-> ///artifact/type.Type Binary (Action Any))
                      (function (_ type content)
                        (promise.future
                         (//.upload repository
@@ -65,8 +67,8 @@
                      (export.library (file.async file.system)
                                      (set.to-list (get@ #/.sources profile))))
          pom (promise@wrap (///pom.project profile))
-         _ (deploy! ///dependency.pom (|> pom (:: xml.codec encode) encoding.to-utf8))
-         _ (deploy! ///dependency.lux-library library)
+         _ (deploy! ///artifact/type.pom (|> pom (:: xml.codec encode) encoding.to-utf8))
+         _ (deploy! ///artifact/type.lux-library library)
          _ (deploy! "sha1" (///hash.sha1 library))
          _ (deploy! "md5" (///hash.md5 library))]
         (wrap [])))))
diff --git a/stdlib/source/program/aedifex/dependency.lux b/stdlib/source/program/aedifex/dependency.lux
index 2086a4d06..3128bb3f3 100644
--- a/stdlib/source/program/aedifex/dependency.lux
+++ b/stdlib/source/program/aedifex/dependency.lux
@@ -1,5 +1,5 @@
 (.module:
-  [lux (#- Name Type)
+  [lux (#- Name)
    ["." host (#+ import:)]
    [abstract
     [monad (#+ do)]
@@ -30,19 +30,16 @@
      ["." uri]]]]
   ["." // #_
    ["#." extension]
-   ["#." artifact (#+ Artifact)]
-   ["#." hash]])
+   ["#." hash]
+   ["#." artifact (#+ Artifact)
+    ["#/." type]]])
 
 (type: #export Repository
   URL)
 
-## https://maven.apache.org/ref/3.6.3/maven-core/artifact-handlers.html
-(type: #export Type
-  Text)
-
 (type: #export Dependency
   {#artifact Artifact
-   #type ..Type})
+   #type //artifact/type.Type})
 
 (def: #export equivalence
   (Equivalence Dependency)
@@ -58,16 +55,6 @@
       text.hash
       ))
 
-(template [<type> <name>]
-  [(def: #export <name>
-     Type
-     <type>)]
-
-  ["tar" lux-library]
-  ["jar" jvm-library]
-  ["pom" pom]
-  )
-
 (import: java/lang/String)
 
 (import: java/lang/AutoCloseable
@@ -200,7 +187,7 @@
                             #//artifact.version version}
                  #type (|> properties
                            (dictionary.get ["" "type"])
-                           (maybe.default ..lux-library))})))))
+                           (maybe.default //artifact/type.lux-library))})))))
 
 (def: parse-dependencies
   (Parser (List Dependency))
diff --git a/stdlib/source/program/aedifex/format.lux b/stdlib/source/program/aedifex/format.lux
index 1107f4d13..4ec8b8ae6 100644
--- a/stdlib/source/program/aedifex/format.lux
+++ b/stdlib/source/program/aedifex/format.lux
@@ -11,8 +11,9 @@
   ["." // #_
    ["/" profile]
    ["#." project (#+ Project)]
-   ["#." artifact (#+ Artifact)]
-   ["#." dependency (#+ Dependency)]])
+   ["#." dependency (#+ Dependency)]
+   ["#." artifact (#+ Artifact)
+    ["#/." type]]])
 
 (type: #export (Format a)
   (-> a Code))
@@ -125,7 +126,7 @@
 
 (def: (dependency [artifact type])
   (Format Dependency)
-  (if (text@= //dependency.lux-library type)
+  (if (text@= //artifact/type.lux-library type)
     (` [(~+ (..artifact' artifact))])
     (` [(~+ (..artifact' artifact))
         (~ (code.text type))])))
diff --git a/stdlib/source/program/aedifex/local.lux b/stdlib/source/program/aedifex/local.lux
index 1b8a02f1a..60b5e8881 100644
--- a/stdlib/source/program/aedifex/local.lux
+++ b/stdlib/source/program/aedifex/local.lux
@@ -32,9 +32,10 @@
    ["/" profile (#+ Profile)]
    ["#." extension]
    ["#." pom]
-   ["#." artifact (#+ Artifact)]
    ["#." dependency (#+ Package Resolution Dependency)]
-   ["#." hash]])
+   ["#." hash]
+   ["#." artifact (#+ Artifact)
+    ["#/." type]]])
 
 (def: (local system)
   (All [a] (-> (file.System a) Path))
@@ -78,7 +79,7 @@
        #let [artifact-name (format repository (:: system separator) (//artifact.identity identity))]
        package (export.library system (set.to-list (get@ #/.sources profile)))
        _ (..save! system (binary.run tar.writer package)
-                  (format artifact-name "." //dependency.lux-library))
+                  (format artifact-name "." //artifact/type.lux-library))
        pom (:: promise.monad wrap (//pom.project profile))]
       (..save! system (|> pom (:: xml.codec encode) encoding.to-utf8)
                (format artifact-name //extension.pom)))
diff --git a/stdlib/source/program/aedifex/parser.lux b/stdlib/source/program/aedifex/parser.lux
index 1799db09e..867b3b81f 100644
--- a/stdlib/source/program/aedifex/parser.lux
+++ b/stdlib/source/program/aedifex/parser.lux
@@ -20,8 +20,9 @@
   ["." // #_
    ["/" profile]
    ["#." project (#+ Project)]
-   ["#." artifact (#+ Artifact)]
-   ["#." dependency]])
+   ["#." dependency]
+   ["#." artifact (#+ Artifact)
+    ["#/." type]]])
 
 (def: (as-input input)
   (-> (Maybe Code) (List Code))
@@ -139,7 +140,7 @@
   ..url)
 
 (def: type
-  (Parser //dependency.Type)
+  (Parser //artifact/type.Type)
   <c>.text)
 
 (def: dependency
@@ -147,7 +148,7 @@
   (<c>.tuple
    ($_ <>.and
        ..artifact'
-       (<>.default //dependency.lux-library ..type)
+       (<>.default //artifact/type.lux-library ..type)
        )))
 
 (def: source
diff --git a/stdlib/source/test/aedifex/artifact.lux b/stdlib/source/test/aedifex/artifact.lux
index 1ba27d0b6..72715fdef 100644
--- a/stdlib/source/test/aedifex/artifact.lux
+++ b/stdlib/source/test/aedifex/artifact.lux
@@ -9,6 +9,8 @@
       ["$." equivalence]]}]
    [math
     ["." random (#+ Random)]]]
+  ["." / #_
+   ["#." type]]
   {#program
    ["." /]})
 
@@ -27,4 +29,6 @@
         ($_ _.and
             (_.with-cover [/.equivalence]
               ($equivalence.spec /.equivalence ..random))
+
+            /type.test
             ))))
diff --git a/stdlib/source/test/aedifex/artifact/type.lux b/stdlib/source/test/aedifex/artifact/type.lux
new file mode 100644
index 000000000..fd815f19e
--- /dev/null
+++ b/stdlib/source/test/aedifex/artifact/type.lux
@@ -0,0 +1,28 @@
+(.module:
+  [lux #*
+   ["_" test (#+ Test)]
+   [abstract
+    [monad (#+ do)]]
+   [data
+    ["." text]
+    [number
+     ["n" nat]]
+    [collection
+     ["." set]
+     ["." list]]]
+   [math
+    ["." random (#+ Random)]]]
+  {#program
+   ["." /]})
+
+(def: #export test
+  Test
+  (<| (_.covering /._)
+      (_.with-cover [/.Type]
+        ($_ _.and
+            (_.cover [/.lux-library /.jvm-library /.pom]
+                     (let [options (list /.lux-library /.jvm-library /.pom)
+                           uniques (set.from-list text.hash options)]
+                       (n.= (list.size options)
+                            (set.size uniques))))
+            ))))
diff --git a/stdlib/source/test/lux/data/product.lux b/stdlib/source/test/lux/data/product.lux
index 20e62ef86..74057ad63 100644
--- a/stdlib/source/test/lux/data/product.lux
+++ b/stdlib/source/test/lux/data/product.lux
@@ -18,6 +18,7 @@
 (def: #export test
   Test
   (<| (_.covering /._)
+      (_.with-cover [.&])
       (do random.monad
         [expected random.nat
          shift random.nat
diff --git a/stdlib/source/test/lux/data/sum.lux b/stdlib/source/test/lux/data/sum.lux
index 972677361..3bbf65bc9 100644
--- a/stdlib/source/test/lux/data/sum.lux
+++ b/stdlib/source/test/lux/data/sum.lux
@@ -22,6 +22,7 @@
 (def: #export test
   Test
   (<| (_.covering /._)
+      (_.with-cover [.|])
       (do {@ random.monad}
         [expected random.nat
          shift random.nat])
diff --git a/stdlib/source/test/lux/data/text.lux b/stdlib/source/test/lux/data/text.lux
index a1a0ec7b1..6fbee6ec5 100644
--- a/stdlib/source/test/lux/data/text.lux
+++ b/stdlib/source/test/lux/data/text.lux
@@ -1,137 +1,295 @@
 (.module:
-  [lux #*
-   ["%" data/text/format (#+ format)]
+  [lux (#- char)
    ["_" test (#+ Test)]
    [abstract
-    [monad (#+ do Monad)]
+    [monad (#+ do)]
     {[0 #spec]
      [/
       ["$." equivalence]
-      ["$." order]]}]
+      ["$." order]
+      ["$." monoid]]}]
    [control
     pipe]
    [data
+    ["." maybe]
     [number
      ["n" nat]]
     [collection
-     ["." list]]]
+     ["." list]
+     ["." set]]]
    [math
-    ["r" random]]]
+    ["." random]]]
   {1
    ["." /]})
 
 (def: bounded-size
-  (r.Random Nat)
-  (|> r.nat
-      (:: r.monad map (|>> (n.% 20) (n.+ 1)))))
+  (random.Random Nat)
+  (|> random.nat
+      (:: random.monad map (|>> (n.% 20) (n.+ 1)))))
 
-(def: #export test
+(def: size
   Test
-  (<| (_.context (%.name (name-of .Text)))
-      ($_ _.and
-          ($equivalence.spec /.equivalence (r.ascii 2))
-          ($order.spec /.order (r.ascii 2))
+  (do {@ random.monad}
+    [size (:: @ map (n.% 10) random.nat)
+     sample (random.unicode size)]
+    ($_ _.and
+        (_.cover [/.size]
+                 (n.= size (/.size sample)))
+        (_.cover [/.empty?]
+                 (or (/.empty? sample)
+                     (not (n.= 0 size)))))))
 
-          (do {@ r.monad}
-            [size (:: @ map (n.% 10) r.nat)
-             sample (r.unicode size)]
-            ($_ _.and
-                (_.test "Can get the size of text."
-                        (n.= size (/.size sample)))
-                (_.test "Text with size 0 is considered 'empty'."
-                        (or (not (n.= 0 size))
-                            (/.empty? sample)))))
-          (do {@ r.monad}
-            [size bounded-size
-             idx (:: @ map (n.% size) r.nat)
-             sample (r.unicode size)]
-            (_.test "Character locations."
-                    (|> sample
-                        (/.nth idx)
-                        (case> (^multi (#.Some char)
-                                       [(/.from-code char) char]
-                                       [[(/.index-of char sample)
-                                         (/.last-index-of char sample)
-                                         (/.index-of' char idx sample)
-                                         (/.last-index-of' char idx sample)]
-                                        [(#.Some io) (#.Some lio)
-                                         (#.Some io') (#.Some lio')]])
-                               (and (n.<= idx io)
-                                    (n.>= idx lio)
+(def: affix
+  Test
+  (do {@ random.monad}
+    [inner (random.unicode 1)
+     outer (random.filter (|>> (:: /.equivalence = inner) not)
+                          (random.unicode 1))
+     left (random.unicode 1)
+     right (random.unicode 1)
+     #let [full (:: /.monoid compose inner outer)
+           fake-index (.nat -1)]]
+    (`` ($_ _.and
+            (~~ (template [<affix> <predicate>]
+                  [(_.cover [<affix> <predicate>]
+                            (<predicate> outer (<affix> outer inner)))]
+
+                  [/.prefix /.starts-with?]
+                  [/.suffix /.ends-with?]
+                  [/.enclose' /.encloses?]
+                  ))
+            (_.cover [/.enclose]
+                     (let [value (/.enclose [left right] inner)]
+                       (and (/.starts-with? left value)
+                            (/.ends-with? right value))))
+            (_.cover [/.encode]
+                     (let [sample (/.encode inner)]
+                       (and (/.encloses? /.double-quote sample)
+                            (/.contains? inner sample))))
+            ))))
+
+(def: index
+  Test
+  (do {@ random.monad}
+    [inner (random.unicode 1)
+     outer (random.filter (|>> (:: /.equivalence = inner) not)
+                          (random.unicode 1))
+     #let [fake-index (.nat -1)]]
+    ($_ _.and
+        (_.cover [/.contains?]
+                 (let [full (:: /.monoid compose inner outer)]
+                   (and (/.contains? inner full)
+                        (/.contains? outer full))))
+        (_.cover [/.index-of]
+                 (and (|> (/.index-of inner (:: /.monoid compose inner outer))
+                          (maybe.default fake-index)
+                          (n.= 0))
+                      (|> (/.index-of outer (:: /.monoid compose inner outer))
+                          (maybe.default fake-index)
+                          (n.= 1))))
+        (_.cover [/.index-of']
+                 (let [full (:: /.monoid compose inner outer)]
+                   (and (|> (/.index-of' inner 0 full)
+                            (maybe.default fake-index)
+                            (n.= 0))
+                        (|> (/.index-of' inner 1 full)
+                            (maybe.default fake-index)
+                            (n.= fake-index))
+                        
+                        (|> (/.index-of' outer 0 full)
+                            (maybe.default fake-index)
+                            (n.= 1))
+                        (|> (/.index-of' outer 1 full)
+                            (maybe.default fake-index)
+                            (n.= 1))
+                        (|> (/.index-of' outer 2 full)
+                            (maybe.default fake-index)
+                            (n.= fake-index)))))
+        (_.cover [/.last-index-of]
+                 (let [full ($_ (:: /.monoid compose) outer inner outer)]
+                   (and (|> (/.last-index-of inner full)
+                            (maybe.default fake-index)
+                            (n.= 1))
+                        (|> (/.last-index-of outer full)
+                            (maybe.default fake-index)
+                            (n.= 2)))))
+        (_.cover [/.last-index-of']
+                 (let [full ($_ (:: /.monoid compose) outer inner outer)]
+                   (and (|> (/.last-index-of' inner 0 full)
+                            (maybe.default fake-index)
+                            (n.= 1))
+                        (|> (/.last-index-of' inner 2 full)
+                            (maybe.default fake-index)
+                            (n.= fake-index))
+                        
+                        (|> (/.last-index-of' outer 0 full)
+                            (maybe.default fake-index)
+                            (n.= 2))
+                        (|> (/.last-index-of' outer 2 full)
+                            (maybe.default fake-index)
+                            (n.= 2))
+                        (|> (/.last-index-of' outer 3 full)
+                            (maybe.default fake-index)
+                            (n.= fake-index)))))
+        )))
+
+(def: char
+  Test
+  ($_ _.and
+      (_.with-cover [/.Char /.from-code]
+        (`` ($_ _.and
+                (~~ (template [<short> <long>]
+                      [(_.cover [<short> <long>]
+                                (:: /.equivalence = <short> <long>))]
 
-                                    (n.= idx io')
-                                    (n.>= idx lio')
+                      [/.\0  /.null]
+                      [/.\a  /.alarm]
+                      [/.\b  /.back-space]
+                      [/.\t  /.tab]
+                      [/.\n  /.new-line]
+                      [/.\v  /.vertical-tab]
+                      [/.\f  /.form-feed]
+                      [/.\r  /.carriage-return]
+                      [/.\'' /.double-quote]))
+                (_.cover [/.line-feed]
+                         (:: /.equivalence = /.new-line /.line-feed))
+                )))
+      (do {@ random.monad}
+        [size (:: @ map (|>> (n.% 10) inc) random.nat)
+         characters (random.set /.hash size (random.ascii/alpha 1))
+         #let [sample (|> characters set.to-list /.concat)]
+         expected (:: @ map (n.% size) random.nat)]
+        (_.cover [/.nth]
+                 (case (/.nth expected sample)
+                   (#.Some char)
+                   (case (/.index-of (/.from-code char) sample)
+                     (#.Some actual)
+                     (n.= expected actual)
 
-                                    (/.contains? char sample))
+                     _
+                     false)
+                   
+                   #.None
+                   false)))
+      (_.cover [/.space /.space?]
+               (`` (and (~~ (template [<char>]
+                              [(/.space? (`` (.char (~~ (static <char>)))))]
+                              
+                              [/.tab]
+                              [/.vertical-tab]
+                              [/.space]
+                              [/.new-line]
+                              [/.carriage-return]
+                              [/.form-feed]
+                              )))))
+      ))
 
-                               _
-                               #0
-                               ))
-                    ))
-          (do r.monad
+(def: manipulation
+  Test
+  (do {@ random.monad}
+    [size (:: @ map (|>> (n.% 10) (n.+ 2)) random.nat)
+     characters (random.set /.hash size (random.ascii/alpha 1))
+     separator (random.filter (|>> (set.member? characters) not)
+                              (random.ascii/alpha 1))
+     #let [with-no-separator (|> characters set.to-list /.concat)]
+     static (random.ascii/alpha 1)
+     #let [dynamic (random.filter (|>> (:: /.equivalence = static) not)
+                                  (random.ascii/alpha 1))]
+     pre dynamic
+     post dynamic]
+    ($_ _.and
+        (_.cover [/.concat]
+                 (n.= (set.size characters)
+                      (/.size (/.concat (set.to-list characters)))))
+        (_.cover [/.join-with /.split-all-with]
+                 (and (|> (set.to-list characters)
+                          (/.join-with separator)
+                          (/.split-all-with separator)
+                          (set.from-list /.hash)
+                          (:: set.equivalence = characters))
+                      (:: /.equivalence =
+                          (/.concat (set.to-list characters))
+                          (/.join-with "" (set.to-list characters)))))
+        (_.cover [/.replace-once]
+                 (:: /.equivalence =
+                     (:: /.monoid compose post static)
+                     (/.replace-once pre post (:: /.monoid compose pre static))))
+        (_.cover [/.split-with]
+                 (case (/.split-with static ($_ (:: /.monoid compose) pre static post))
+                   (#.Some [left right])
+                   (and (:: /.equivalence = pre left)
+                        (:: /.equivalence = post right))
+                   
+                   #.None
+                   false))
+        )))
+
+(def: #export test
+  Test
+  (<| (_.covering /._)
+      (_.with-cover [.Text])
+      ($_ _.and
+          (_.with-cover [/.equivalence]
+            ($equivalence.spec /.equivalence (random.ascii 2)))
+          (_.with-cover [/.order]
+            ($order.spec /.order (random.ascii 2)))
+          (_.with-cover [/.monoid]
+            ($monoid.spec /.equivalence /.monoid (random.ascii 2)))
+
+          ..size
+          ..affix
+          ..index
+          ..char
+          ..manipulation
+          
+          (do random.monad
             [sizeL bounded-size
              sizeR bounded-size
-             sampleL (r.unicode sizeL)
-             sampleR (r.unicode sizeR)
+             sampleL (random.unicode sizeL)
+             sampleR (random.unicode sizeR)
+             middle (random.unicode 1)
              #let [sample (/.concat (list sampleL sampleR))
                    (^open "/@.") /.equivalence]]
             ($_ _.and
-                (_.test "Can join text snippets."
-                        (and (not (/@= sample
-                                       (/.join-with " " (list sampleL sampleR))))
-                             (/@= sample
-                                  (/.join-with "" (list sampleL sampleR)))))
-                (_.test "Can check sub-texts at the borders."
-                        (and (/.starts-with? sampleL sample)
-                             (/.ends-with? sampleR sample)))
-                (_.test "Can enclose text in another texts."
-                        (/@= (/.enclose [sampleR sampleR] sampleL)
-                             (/.enclose' sampleR sampleL)))
-                (_.test "Can split text."
-                        (|> (/.split sizeL sample)
-                            (case> (#.Right [_l _r])
-                                   (and (/@= sampleL _l)
-                                        (/@= sampleR _r)
-                                        (/@= sample (/.concat (list _l _r))))
+                (_.cover [/.split]
+                         (|> (/.split sizeL sample)
+                             (case> (#.Right [_l _r])
+                                    (and (/@= sampleL _l)
+                                         (/@= sampleR _r)
+                                         (/@= sample (/.concat (list _l _r))))
 
-                                   _
-                                   #0)))
-                (_.test "Can clip text."
-                        (|> [(/.clip 0 sizeL sample)
-                             (/.clip sizeL (/.size sample) sample)
-                             (/.clip' sizeL sample)
-                             (/.clip' 0 sample)]
-                            (case> [(#.Right _l) (#.Right _r) (#.Right _r') (#.Right _f)]
-                                   (and (/@= sampleL _l)
-                                        (/@= sampleR _r)
-                                        (/@= _r _r')
-                                        (/@= sample _f))
+                                    _
+                                    #0)))
+                (_.cover [/.clip /.clip']
+                         (|> [(/.clip 0 sizeL sample)
+                              (/.clip sizeL (/.size sample) sample)
+                              (/.clip' sizeL sample)
+                              (/.clip' 0 sample)]
+                             (case> [(#.Right _l) (#.Right _r) (#.Right _r') (#.Right _f)]
+                                    (and (/@= sampleL _l)
+                                         (/@= sampleR _r)
+                                         (/@= _r _r')
+                                         (/@= sample _f))
 
-                                   _
-                                   #0)))
+                                    _
+                                    #0)))
                 ))
-          (do {@ r.monad}
+          (do {@ random.monad}
             [sizeP bounded-size
              sizeL bounded-size
              #let [## The wider unicode charset includes control characters that
                    ## can make text replacement work improperly.
                    ## Because of that, I restrict the charset.
-                   normal-char-gen (|> r.nat (:: @ map (|>> (n.% 128) (n.max 1))))]
-             sep1 (r.text normal-char-gen 1)
-             sep2 (r.text normal-char-gen 1)
-             #let [part-gen (|> (r.text normal-char-gen sizeP)
-                                (r.filter (|>> (/.contains? sep1) not)))]
-             parts (r.list sizeL part-gen)
+                   normal-char-gen (|> random.nat (:: @ map (|>> (n.% 128) (n.max 1))))]
+             sep1 (random.text normal-char-gen 1)
+             sep2 (random.text normal-char-gen 1)
+             #let [part-gen (|> (random.text normal-char-gen sizeP)
+                                (random.filter (|>> (/.contains? sep1) not)))]
+             parts (random.list sizeL part-gen)
              #let [sample1 (/.concat (list.interpose sep1 parts))
                    sample2 (/.concat (list.interpose sep2 parts))
                    (^open "/@.") /.equivalence]]
-            ($_ _.and
-                (_.test "Can split text multiple times through a separator."
-                        (n.= (list.size parts)
-                             (list.size (/.split-all-with sep1 sample1))))
-
-                (_.test "Can replace occurrences of a piece of text inside a larger text."
-                        (/@= sample2
-                             (/.replace-all sep1 sep2 sample1)))
-                ))
+            (_.cover [/.replace-all]
+                     (/@= sample2
+                          (/.replace-all sep1 sep2 sample1))))
           )))
diff --git a/stdlib/source/test/lux/target/jvm.lux b/stdlib/source/test/lux/target/jvm.lux
index b9639a82f..e1c4dbfe3 100644
--- a/stdlib/source/test/lux/target/jvm.lux
+++ b/stdlib/source/test/lux/target/jvm.lux
@@ -237,6 +237,11 @@
    #random ..$Float::random
    #literal ..$Float::literal})
 
+(def: valid-float
+  (Random java/lang/Float)
+  (random.filter (|>> host.float-to-double (:coerce Frac) f.not-a-number? not)
+                 ..$Float::random))
+
 (def: $Double (/type.class "java.lang.Double" (list)))
 (def: $Double::wrap (/.invokestatic ..$Double "valueOf" (/type.method [(list /type.double) ..$Double (list)])))
 (def: $Double::random (:coerce (Random java/lang/Double) random.frac))
@@ -678,10 +683,8 @@
         comparison (: (-> (Bytecode Any) (-> java/lang/Double java/lang/Double Bit) (Random Bit))
                       (function (_ instruction standard)
                         (do random.monad
-                          [#let [valid-double (random.filter (|>> (:coerce Frac) f.not-a-number? not)
-                                                             ..$Double::random)]
-                           reference valid-double
-                           subject valid-double
+                          [reference ..valid-double
+                           subject ..valid-double
                            #let [expected (if (for {@.old
                                                     ("jvm deq" reference subject)
                                                     
@@ -1184,15 +1187,15 @@
             (let [test (!::= java/lang/Float "jvm feq" "jvm float =")]
               ($_ _.and
                   (_.lift "FSTORE_0/FLOAD_0"
-                          (store-and-load ..$Float::random ..$Float::literal ..$Float::wrap [(function.constant /.fstore-0) (function.constant /.fload-0)] test))
+                          (store-and-load ..valid-float ..$Float::literal ..$Float::wrap [(function.constant /.fstore-0) (function.constant /.fload-0)] test))
                   (_.lift "FSTORE_1/FLOAD_1"
-                          (store-and-load ..$Float::random ..$Float::literal ..$Float::wrap [(function.constant /.fstore-1) (function.constant /.fload-1)] test))
+                          (store-and-load ..valid-float ..$Float::literal ..$Float::wrap [(function.constant /.fstore-1) (function.constant /.fload-1)] test))
                   (_.lift "FSTORE_2/FLOAD_2"
-                          (store-and-load ..$Float::random ..$Float::literal ..$Float::wrap [(function.constant /.fstore-2) (function.constant /.fload-2)] test))
+                          (store-and-load ..valid-float ..$Float::literal ..$Float::wrap [(function.constant /.fstore-2) (function.constant /.fload-2)] test))
                   (_.lift "FSTORE_3/FLOAD_3"
-                          (store-and-load ..$Float::random ..$Float::literal ..$Float::wrap [(function.constant /.fstore-3) (function.constant /.fload-3)] test))
+                          (store-and-load ..valid-float ..$Float::literal ..$Float::wrap [(function.constant /.fstore-3) (function.constant /.fload-3)] test))
                   (_.lift "FSTORE/FLOAD"
-                          (store-and-load ..$Float::random ..$Float::literal ..$Float::wrap [/.fstore /.fload] test)))))
+                          (store-and-load ..valid-float ..$Float::literal ..$Float::wrap [/.fstore /.fload] test)))))
         (<| (_.context "double")
             (let [test (!::= java/lang/Double "jvm deq" "jvm double =")]
               ($_ _.and