Generate OPAM files from dune-project

This has some advantages, e.g. auto-generating the correct dune
incantation as well as deduplicating some of the OPAM stanzas.

dune-project

@@ -1,3 +1,38 @@
 (lang dune 2.7)
 (name yojson)
 (formatting (enabled_for dune))
+
+(generate_opam_files true)
+(source (github ocaml-community/yojson))
+(license BSD-3-Clause)
+
+(maintainers "[email protected]" "[email protected]" "[email protected]")
+(authors "Martin Jambon")
+(documentation "https://ocaml-community.github.io/yojson")
+
+(package
+  (name yojson)
+  (synopsis "Yojson is an optimized parsing and printing library for the JSON format")
+  (description "Yojson is an optimized parsing and printing library for the JSON format.
+
+ydump is a pretty-printing command-line program provided with the
+yojson package.")
+  (depends
+    (ocaml (>= 4.02.3))
+    (cppo :build)
+    (alcotest (and :with-test (>= 0.8.5)))
+    (seq (>= 0.2.2))))
+
+(package
+  (name yojson-bench)
+  (synopsis "Run Yojson benchmarks")
+  (description "Yojson benchmarks require `Core_bench` which is not a dependency of Yojson,
+because it is not part of the regular installation/testing flow. This is solely
+meant for developers that are worried about performance changes in Yojson.")
+  (depends
+    (ocaml (>= 4.08))
+    (yojson (= :version))
+    (core_bench (>= v0.15.0))
+    (core (>= v0.14.0))
+    (core_unix (>= v0.14.0))
+    (sexplib (>= v0.9.0))))

yojson-bench.opam

@@ -1,26 +1,40 @@
+# This file is generated by dune, edit dune-project instead
 opam-version: "2.0"
-maintainer: ["[email protected]" "[email protected]" "[email protected]"]
+synopsis: "Run Yojson benchmarks"
+description: """
+Yojson benchmarks require `Core_bench` which is not a dependency of Yojson,
+because it is not part of the regular installation/testing flow. This is solely
+meant for developers that are worried about performance changes in Yojson."""
+maintainer: [
+  "[email protected]" "[email protected]" "[email protected]"
+]
 authors: ["Martin Jambon"]
+license: "BSD-3-Clause"
 homepage: "https://github.com/ocaml-community/yojson"
+doc: "https://ocaml-community.github.io/yojson"
 bug-reports: "https://github.com/ocaml-community/yojson/issues"
-dev-repo: "git+https://github.com/ocaml-community/yojson.git"
-doc: "https://ocaml-community.github.io/yojson/"
-license: "BSD-3-Clause"
 depends: [
+  "dune" {>= "2.7"}
   "ocaml" {>= "4.08"}
   "yojson" {= version}
-  "dune" {>= "2.7.0"}
   "core_bench" {>= "v0.15.0"}
   "core" {>= "v0.14.0"}
   "core_unix" {>= "v0.14.0"}
   "sexplib" {>= "v0.9.0"}
+  "odoc" {with-doc}
 ]
 build: [
   ["dune" "subst"] {dev}
-  ["dune" "build" "-p" name "-j" jobs]
+  [
+    "dune"
+    "build"
+    "-p"
+    name
+    "-j"
+    jobs
+    "@install"
+    "@runtest" {with-test}
+    "@doc" {with-doc}
+  ]
 ]
-synopsis: "Run Yojson benchmarks"
-description: """\
-Yojson benchmarks require `Core_bench` which is not a dependency of Yojson,
-because it is not part of the regular installation/testing flow. This is solely
-meant for developers that are worried about performance changes in Yojson."""
+dev-repo: "git+https://github.com/ocaml-community/yojson.git"

yojson.opam

@@ -1,29 +1,40 @@
+# This file is generated by dune, edit dune-project instead
 opam-version: "2.0"
-maintainer: ["[email protected]" "[email protected]"]
+synopsis:
+  "Yojson is an optimized parsing and printing library for the JSON format"
+description: """
+Yojson is an optimized parsing and printing library for the JSON format.
+
+ydump is a pretty-printing command-line program provided with the
+yojson package."""
+maintainer: [
+  "[email protected]" "[email protected]" "[email protected]"
+]
 authors: ["Martin Jambon"]
+license: "BSD-3-Clause"
 homepage: "https://github.com/ocaml-community/yojson"
+doc: "https://ocaml-community.github.io/yojson"
 bug-reports: "https://github.com/ocaml-community/yojson/issues"
-dev-repo: "git+https://github.com/ocaml-community/yojson.git"
-doc: "https://ocaml-community.github.io/yojson/"
-license: "BSD-3-Clause"
-build: [
-  ["dune" "subst"] {dev}
-  ["dune" "build" "-p" name "-j" jobs]
-  ["dune" "runtest" "-p" name "-j" jobs] {with-test}
-  ["dune" "build" "@doc" "-p" name "-j" jobs] {with-doc}
-]
 depends: [
+  "dune" {>= "2.7"}
   "ocaml" {>= "4.02.3"}
-  "dune" {>= "2.7.0"}
   "cppo" {build}
   "alcotest" {with-test & >= "0.8.5"}
-  "odoc" {with-doc}
   "seq" {>= "0.2.2"}
+  "odoc" {with-doc}
 ]
-synopsis:
-  "Yojson is an optimized parsing and printing library for the JSON format"
-description: """
-Yojson is an optimized parsing and printing library for the JSON format.
-
-ydump is a pretty-printing command-line program provided with the
-yojson package."""
+build: [
+  ["dune" "subst"] {dev}
+  [
+    "dune"
+    "build"
+    "-p"
+    name
+    "-j"
+    jobs
+    "@install"
+    "@runtest" {with-test}
+    "@doc" {with-doc}
+  ]
+]
+dev-repo: "git+https://github.com/ocaml-community/yojson.git"